user_guide/database/db_driver_reference.html



<!DOCTYPE html>
<!--[if IE 8]><html class="no-js lt-ie9" lang="en" > <![endif]-->
<!--[if gt IE 8]><!--> <html class="no-js" lang="en" > <!--<![endif]-->
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  
  <title>DB Driver Reference &mdash; CodeIgniter 3.1.6 documentation</title>
  

    <link rel="shortcut icon" href="../_static/ci-icon.ico"/>
  

  <link href='https://fonts.googleapis.com/css?family=Lato:400,700,400italic,700italic|Roboto+Slab:400,700|Inconsolata:400,700&subset=latin,cyrillic' rel='stylesheet' type='text/css'>

  
    <link rel="stylesheet" href="../_static/css/citheme.css" type="text/css" />
  

        <link rel="index" title="Index"
              href="../genindex.html"/>
        <link rel="search" title="Search" href="../search.html"/>
    <link rel="top" title="CodeIgniter 3.1.6 documentation" href="../index.html"/>
        <link rel="up" title="Database Reference" href="index.html"/>
        <link rel="next" title="Helpers" href="../helpers/index.html"/>
        <link rel="prev" title="Database Utility Class" href="utilities.html"/> 

  
  <script src="https://cdnjs.cloudflare.com/ajax/libs/modernizr/2.6.2/modernizr.min.js"></script>

</head>

<body class="wy-body-for-nav" role="document">

  <div id="nav">
  <div id="nav_inner">
    
    
      <div id="pulldown-menu" class="ciNav">
        <ul>
<li class="toctree-l1"><a class="reference internal" href="../general/welcome.html">Welcome to CodeIgniter</a></li>
</ul>
<ul>
<li class="toctree-l1"><a class="reference internal" href="../installation/index.html">Installation Instructions</a><ul>
<li class="toctree-l2"><a class="reference internal" href="../installation/downloads.html">Downloading CodeIgniter</a></li>
<li class="toctree-l2"><a class="reference internal" href="../installation/index.html">Installation Instructions</a></li>
<li class="toctree-l2"><a class="reference internal" href="../installation/upgrading.html">Upgrading From a Previous Version</a></li>
<li class="toctree-l2"><a class="reference internal" href="../installation/troubleshooting.html">Troubleshooting</a></li>
</ul>
</li>
</ul>
<ul>
<li class="toctree-l1"><a class="reference internal" href="../overview/index.html">CodeIgniter Overview</a><ul>
<li class="toctree-l2"><a class="reference internal" href="../overview/getting_started.html">Getting Started</a></li>
<li class="toctree-l2"><a class="reference internal" href="../overview/at_a_glance.html">CodeIgniter at a Glance</a></li>
<li class="toctree-l2"><a class="reference internal" href="../overview/features.html">Supported Features</a></li>
<li class="toctree-l2"><a class="reference internal" href="../overview/appflow.html">Application Flow Chart</a></li>
<li class="toctree-l2"><a class="reference internal" href="../overview/mvc.html">Model-View-Controller</a></li>
<li class="toctree-l2"><a class="reference internal" href="../overview/goals.html">Architectural Goals</a></li>
</ul>
</li>
</ul>
<ul>
<li class="toctree-l1"><a class="reference internal" href="../tutorial/index.html">Tutorial</a><ul>
<li class="toctree-l2"><a class="reference internal" href="../tutorial/static_pages.html">Static pages</a></li>
<li class="toctree-l2"><a class="reference internal" href="../tutorial/news_section.html">News section</a></li>
<li class="toctree-l2"><a class="reference internal" href="../tutorial/create_news_items.html">Create news items</a></li>
<li class="toctree-l2"><a class="reference internal" href="../tutorial/conclusion.html">Conclusion</a></li>
</ul>
</li>
</ul>
<ul>
<li class="toctree-l1"><a class="reference internal" href="../contributing/index.html">Contributing to CodeIgniter</a><ul>
<li class="toctree-l2"><a class="reference internal" href="../documentation/index.html">Writing CodeIgniter Documentation</a></li>
<li class="toctree-l2"><a class="reference internal" href="../DCO.html">Developer’s Certificate of Origin 1.1</a></li>
</ul>
</li>
</ul>
<ul>
<li class="toctree-l1"><a class="reference internal" href="../general/index.html">General Topics</a><ul>
<li class="toctree-l2"><a class="reference internal" href="../general/urls.html">CodeIgniter URLs</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/controllers.html">Controllers</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/reserved_names.html">Reserved Names</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/views.html">Views</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/models.html">Models</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/helpers.html">Helpers</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/libraries.html">Using CodeIgniter Libraries</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/creating_libraries.html">Creating Libraries</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/drivers.html">Using CodeIgniter Drivers</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/creating_drivers.html">Creating Drivers</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/core_classes.html">Creating Core System Classes</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/ancillary_classes.html">Creating Ancillary Classes</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/hooks.html">Hooks - Extending the Framework Core</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/autoloader.html">Auto-loading Resources</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/common_functions.html">Common Functions</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/compatibility_functions.html">Compatibility Functions</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/routing.html">URI Routing</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/errors.html">Error Handling</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/caching.html">Caching</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/profiling.html">Profiling Your Application</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/cli.html">Running via the CLI</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/managing_apps.html">Managing your Applications</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/environments.html">Handling Multiple Environments</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/alternative_php.html">Alternate PHP Syntax for View Files</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/security.html">Security</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/styleguide.html">PHP Style Guide</a></li>
</ul>
</li>
</ul>
<ul>
<li class="toctree-l1"><a class="reference internal" href="../libraries/index.html">Libraries</a><ul>
<li class="toctree-l2"><a class="reference internal" href="../libraries/benchmark.html">Benchmarking Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/caching.html">Caching Driver</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/calendar.html">Calendaring Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/cart.html">Shopping Cart Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/config.html">Config Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/email.html">Email Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/encrypt.html">Encrypt Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/encryption.html">Encryption Library</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/file_uploading.html">File Uploading Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/form_validation.html">Form Validation</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/ftp.html">FTP Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/image_lib.html">Image Manipulation Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/input.html">Input Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/javascript.html">Javascript Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/language.html">Language Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/loader.html">Loader Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/migration.html">Migrations Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/output.html">Output Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/pagination.html">Pagination Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/parser.html">Template Parser Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/security.html">Security Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/sessions.html">Session Library</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/table.html">HTML Table Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/trackback.html">Trackback Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/typography.html">Typography Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/unit_testing.html">Unit Testing Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/uri.html">URI Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/user_agent.html">User Agent Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/xmlrpc.html">XML-RPC and XML-RPC Server Classes</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/zip.html">Zip Encoding Class</a></li>
</ul>
</li>
</ul>
<ul class="current">
<li class="toctree-l1 current"><a class="reference internal" href="index.html">Database Reference</a><ul class="current">
<li class="toctree-l2"><a class="reference internal" href="examples.html">Quick Start: Usage Examples</a></li>
<li class="toctree-l2"><a class="reference internal" href="configuration.html">Database Configuration</a></li>
<li class="toctree-l2"><a class="reference internal" href="connecting.html">Connecting to a Database</a></li>
<li class="toctree-l2"><a class="reference internal" href="queries.html">Running Queries</a></li>
<li class="toctree-l2"><a class="reference internal" href="results.html">Generating Query Results</a></li>
<li class="toctree-l2"><a class="reference internal" href="helpers.html">Query Helper Functions</a></li>
<li class="toctree-l2"><a class="reference internal" href="query_builder.html">Query Builder Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="transactions.html">Transactions</a></li>
<li class="toctree-l2"><a class="reference internal" href="metadata.html">Getting MetaData</a></li>
<li class="toctree-l2"><a class="reference internal" href="call_function.html">Custom Function Calls</a></li>
<li class="toctree-l2"><a class="reference internal" href="caching.html">Query Caching</a></li>
<li class="toctree-l2"><a class="reference internal" href="forge.html">Database Manipulation with Database Forge</a></li>
<li class="toctree-l2"><a class="reference internal" href="utilities.html">Database Utilities Class</a></li>
<li class="toctree-l2 current"><a class="current reference internal" href="#">Database Driver Reference</a></li>
</ul>
</li>
</ul>
<ul>
<li class="toctree-l1"><a class="reference internal" href="../helpers/index.html">Helpers</a><ul>
<li class="toctree-l2"><a class="reference internal" href="../helpers/array_helper.html">Array Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/captcha_helper.html">CAPTCHA Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/cookie_helper.html">Cookie Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/date_helper.html">Date Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/directory_helper.html">Directory Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/download_helper.html">Download Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/email_helper.html">Email Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/file_helper.html">File Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/form_helper.html">Form Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/html_helper.html">HTML Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/inflector_helper.html">Inflector Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/language_helper.html">Language Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/number_helper.html">Number Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/path_helper.html">Path Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/security_helper.html">Security Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/smiley_helper.html">Smiley Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/string_helper.html">String Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/text_helper.html">Text Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/typography_helper.html">Typography Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/url_helper.html">URL Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/xml_helper.html">XML Helper</a></li>
</ul>
</li>
</ul>

      </div>
    
      
  </div>
</div>
<div id="nav2">
  <a href="#" id="openToc">
    <img src="data:image/jpeg;base64,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" title="Toggle Table of Contents" alt="Toggle Table of Contents" />
  </a>
</div>

  <div class="wy-grid-for-nav">

    
    <nav data-toggle="wy-nav-shift" class="wy-nav-side">
      <div class="wy-side-nav-search">
        
          <a href="../index.html" class="fa fa-home"> CodeIgniter</a>
        
        
<div role="search">
  <form id="rtd-search-form" class="wy-form" action="../search.html" method="get">
    <input type="text" name="q" placeholder="Search docs" />
    <input type="hidden" name="check_keywords" value="yes" />
    <input type="hidden" name="area" value="default" />
  </form>
</div>
      </div>

      <div class="wy-menu wy-menu-vertical" data-spy="affix" role="navigation" aria-label="main navigation">
        
          
              <ul>
<li class="toctree-l1"><a class="reference internal" href="../general/welcome.html">Welcome to CodeIgniter</a></li>
</ul>
<ul>
<li class="toctree-l1"><a class="reference internal" href="../installation/index.html">Installation Instructions</a><ul>
<li class="toctree-l2"><a class="reference internal" href="../installation/downloads.html">Downloading CodeIgniter</a></li>
<li class="toctree-l2"><a class="reference internal" href="../installation/index.html">Installation Instructions</a></li>
<li class="toctree-l2"><a class="reference internal" href="../installation/upgrading.html">Upgrading From a Previous Version</a></li>
<li class="toctree-l2"><a class="reference internal" href="../installation/troubleshooting.html">Troubleshooting</a></li>
</ul>
</li>
</ul>
<ul>
<li class="toctree-l1"><a class="reference internal" href="../overview/index.html">CodeIgniter Overview</a><ul>
<li class="toctree-l2"><a class="reference internal" href="../overview/getting_started.html">Getting Started</a></li>
<li class="toctree-l2"><a class="reference internal" href="../overview/at_a_glance.html">CodeIgniter at a Glance</a></li>
<li class="toctree-l2"><a class="reference internal" href="../overview/features.html">Supported Features</a></li>
<li class="toctree-l2"><a class="reference internal" href="../overview/appflow.html">Application Flow Chart</a></li>
<li class="toctree-l2"><a class="reference internal" href="../overview/mvc.html">Model-View-Controller</a></li>
<li class="toctree-l2"><a class="reference internal" href="../overview/goals.html">Architectural Goals</a></li>
</ul>
</li>
</ul>
<ul>
<li class="toctree-l1"><a class="reference internal" href="../tutorial/index.html">Tutorial</a><ul>
<li class="toctree-l2"><a class="reference internal" href="../tutorial/static_pages.html">Static pages</a></li>
<li class="toctree-l2"><a class="reference internal" href="../tutorial/news_section.html">News section</a></li>
<li class="toctree-l2"><a class="reference internal" href="../tutorial/create_news_items.html">Create news items</a></li>
<li class="toctree-l2"><a class="reference internal" href="../tutorial/conclusion.html">Conclusion</a></li>
</ul>
</li>
</ul>
<ul>
<li class="toctree-l1"><a class="reference internal" href="../contributing/index.html">Contributing to CodeIgniter</a><ul>
<li class="toctree-l2"><a class="reference internal" href="../documentation/index.html">Writing CodeIgniter Documentation</a></li>
<li class="toctree-l2"><a class="reference internal" href="../DCO.html">Developer’s Certificate of Origin 1.1</a></li>
</ul>
</li>
</ul>
<ul>
<li class="toctree-l1"><a class="reference internal" href="../general/index.html">General Topics</a><ul>
<li class="toctree-l2"><a class="reference internal" href="../general/urls.html">CodeIgniter URLs</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/controllers.html">Controllers</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/reserved_names.html">Reserved Names</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/views.html">Views</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/models.html">Models</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/helpers.html">Helpers</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/libraries.html">Using CodeIgniter Libraries</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/creating_libraries.html">Creating Libraries</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/drivers.html">Using CodeIgniter Drivers</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/creating_drivers.html">Creating Drivers</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/core_classes.html">Creating Core System Classes</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/ancillary_classes.html">Creating Ancillary Classes</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/hooks.html">Hooks - Extending the Framework Core</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/autoloader.html">Auto-loading Resources</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/common_functions.html">Common Functions</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/compatibility_functions.html">Compatibility Functions</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/routing.html">URI Routing</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/errors.html">Error Handling</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/caching.html">Caching</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/profiling.html">Profiling Your Application</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/cli.html">Running via the CLI</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/managing_apps.html">Managing your Applications</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/environments.html">Handling Multiple Environments</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/alternative_php.html">Alternate PHP Syntax for View Files</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/security.html">Security</a></li>
<li class="toctree-l2"><a class="reference internal" href="../general/styleguide.html">PHP Style Guide</a></li>
</ul>
</li>
</ul>
<ul>
<li class="toctree-l1"><a class="reference internal" href="../libraries/index.html">Libraries</a><ul>
<li class="toctree-l2"><a class="reference internal" href="../libraries/benchmark.html">Benchmarking Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/caching.html">Caching Driver</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/calendar.html">Calendaring Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/cart.html">Shopping Cart Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/config.html">Config Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/email.html">Email Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/encrypt.html">Encrypt Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/encryption.html">Encryption Library</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/file_uploading.html">File Uploading Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/form_validation.html">Form Validation</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/ftp.html">FTP Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/image_lib.html">Image Manipulation Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/input.html">Input Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/javascript.html">Javascript Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/language.html">Language Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/loader.html">Loader Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/migration.html">Migrations Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/output.html">Output Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/pagination.html">Pagination Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/parser.html">Template Parser Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/security.html">Security Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/sessions.html">Session Library</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/table.html">HTML Table Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/trackback.html">Trackback Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/typography.html">Typography Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/unit_testing.html">Unit Testing Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/uri.html">URI Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/user_agent.html">User Agent Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/xmlrpc.html">XML-RPC and XML-RPC Server Classes</a></li>
<li class="toctree-l2"><a class="reference internal" href="../libraries/zip.html">Zip Encoding Class</a></li>
</ul>
</li>
</ul>
<ul class="current">
<li class="toctree-l1 current"><a class="reference internal" href="index.html">Database Reference</a><ul class="current">
<li class="toctree-l2"><a class="reference internal" href="examples.html">Quick Start: Usage Examples</a></li>
<li class="toctree-l2"><a class="reference internal" href="configuration.html">Database Configuration</a></li>
<li class="toctree-l2"><a class="reference internal" href="connecting.html">Connecting to a Database</a></li>
<li class="toctree-l2"><a class="reference internal" href="queries.html">Running Queries</a></li>
<li class="toctree-l2"><a class="reference internal" href="results.html">Generating Query Results</a></li>
<li class="toctree-l2"><a class="reference internal" href="helpers.html">Query Helper Functions</a></li>
<li class="toctree-l2"><a class="reference internal" href="query_builder.html">Query Builder Class</a></li>
<li class="toctree-l2"><a class="reference internal" href="transactions.html">Transactions</a></li>
<li class="toctree-l2"><a class="reference internal" href="metadata.html">Getting MetaData</a></li>
<li class="toctree-l2"><a class="reference internal" href="call_function.html">Custom Function Calls</a></li>
<li class="toctree-l2"><a class="reference internal" href="caching.html">Query Caching</a></li>
<li class="toctree-l2"><a class="reference internal" href="forge.html">Database Manipulation with Database Forge</a></li>
<li class="toctree-l2"><a class="reference internal" href="utilities.html">Database Utilities Class</a></li>
<li class="toctree-l2 current"><a class="current reference internal" href="#">Database Driver Reference</a></li>
</ul>
</li>
</ul>
<ul>
<li class="toctree-l1"><a class="reference internal" href="../helpers/index.html">Helpers</a><ul>
<li class="toctree-l2"><a class="reference internal" href="../helpers/array_helper.html">Array Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/captcha_helper.html">CAPTCHA Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/cookie_helper.html">Cookie Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/date_helper.html">Date Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/directory_helper.html">Directory Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/download_helper.html">Download Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/email_helper.html">Email Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/file_helper.html">File Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/form_helper.html">Form Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/html_helper.html">HTML Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/inflector_helper.html">Inflector Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/language_helper.html">Language Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/number_helper.html">Number Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/path_helper.html">Path Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/security_helper.html">Security Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/smiley_helper.html">Smiley Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/string_helper.html">String Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/text_helper.html">Text Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/typography_helper.html">Typography Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/url_helper.html">URL Helper</a></li>
<li class="toctree-l2"><a class="reference internal" href="../helpers/xml_helper.html">XML Helper</a></li>
</ul>
</li>
</ul>

          
      </div>
      &nbsp;
    </nav>

    <section data-toggle="wy-nav-shift" class="wy-nav-content-wrap">

      
      <nav class="wy-nav-top" role="navigation" aria-label="top navigation">
        <i data-toggle="wy-nav-top" class="fa fa-bars"></i>
        <a href="../index.html">CodeIgniter</a>
      </nav>


      <div class="wy-nav-content">
        <div class="rst-content">
          <div role="navigation" aria-label="breadcrumbs navigation">
  <ul class="wy-breadcrumbs">
    <li><a href="../index.html">Docs</a> &raquo;</li>
      
        <li><a href="index.html">Database Reference</a> &raquo;</li>
      
    <li>DB Driver Reference</li>
    <li class="wy-breadcrumbs-aside">
      
    </li>
    <div style="float:right;margin-left:5px;" id="closeMe">
      <img title="Classic Layout" alt="classic layout" src="data:image/gif;base64,R0lGODlhFAAUAJEAAAAAADMzM////wAAACH5BAUUAAIALAAAAAAUABQAAAImlI+py+0PU5gRBRDM3DxbWoXis42X13USOLauUIqnlsaH/eY6UwAAOw==" />
    </div>
  </ul>
  <hr/>
</div>
          <div role="main" class="document">
            
  <div class="section" id="db-driver-reference">
<h1>DB Driver Reference<a class="headerlink" href="#db-driver-reference" title="Permalink to this headline">¶</a></h1>
<p>This is the platform-independent base DB implementation class.
This class will not be called directly. Rather, the adapter
class for the specific database will extend and instantiate it.</p>
<p>The how-to material for this has been split over several articles.
This article is intended to be a reference for them.</p>
<div class="admonition important">
<p class="first admonition-title">Important</p>
<p class="last">Not all methods are supported by all database drivers,
some of them may fail (and return FALSE) if the underlying
driver does not support them.</p>
</div>
<dl class="class">
<dt id="CI_DB_driver">
<em class="property">class </em><code class="descname">CI_DB_driver</code><a class="headerlink" href="#CI_DB_driver" title="Permalink to this definition">¶</a></dt>
<dd><dl class="method">
<dt id="CI_DB_driver::initialize">
<code class="descname">initialize</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::initialize" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Returns:</th><td class="field-body">TRUE on success, FALSE on failure</td>
</tr>
<tr class="field-even field"><th class="field-name">Return type:</th><td class="field-body">bool</td>
</tr>
</tbody>
</table>
<p>Initialize database settings, establish a connection to
the database.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::db_connect">
<code class="descname">db_connect</code><span class="sig-paren">(</span><em>$persistent = TRUE</em><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::db_connect" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$persistent</strong> (<em>bool</em>) – Whether to establish a persistent connection or a regular one</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">Database connection resource/object or FALSE on failure</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">mixed</p>
</td>
</tr>
</tbody>
</table>
<p>Establish a connection with the database.</p>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">The returned value depends on the underlying
driver in use. For example, a <code class="docutils literal"><span class="pre">mysqli</span></code> instance
will be returned with the ‘mysqli’ driver.</p>
</div>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::db_pconnect">
<code class="descname">db_pconnect</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::db_pconnect" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Returns:</th><td class="field-body">Database connection resource/object or FALSE on failure</td>
</tr>
<tr class="field-even field"><th class="field-name">Return type:</th><td class="field-body">mixed</td>
</tr>
</tbody>
</table>
<p>Establish a persistent connection with the database.</p>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">This method is just an alias for <code class="docutils literal"><span class="pre">db_connect(TRUE)</span></code>.</p>
</div>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::reconnect">
<code class="descname">reconnect</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::reconnect" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Returns:</th><td class="field-body">TRUE on success, FALSE on failure</td>
</tr>
<tr class="field-even field"><th class="field-name">Return type:</th><td class="field-body">bool</td>
</tr>
</tbody>
</table>
<p>Keep / reestablish the database connection if no queries
have been sent for a length of time exceeding the
server’s idle timeout.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::db_select">
<code class="descname">db_select</code><span class="sig-paren">(</span><span class="optional">[</span><em>$database = ''</em><span class="optional">]</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::db_select" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$database</strong> (<em>string</em>) – Database name</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">TRUE on success, FALSE on failure</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">bool</p>
</td>
</tr>
</tbody>
</table>
<p>Select / switch the current database.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::db_set_charset">
<code class="descname">db_set_charset</code><span class="sig-paren">(</span><em>$charset</em><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::db_set_charset" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$charset</strong> (<em>string</em>) – Character set name</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">TRUE on success, FALSE on failure</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">bool</p>
</td>
</tr>
</tbody>
</table>
<p>Set client character set.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::platform">
<code class="descname">platform</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::platform" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Returns:</th><td class="field-body">Platform name</td>
</tr>
<tr class="field-even field"><th class="field-name">Return type:</th><td class="field-body">string</td>
</tr>
</tbody>
</table>
<p>The name of the platform in use (mysql, mssql, etc…).</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::version">
<code class="descname">version</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::version" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Returns:</th><td class="field-body">The version of the database being used</td>
</tr>
<tr class="field-even field"><th class="field-name">Return type:</th><td class="field-body">string</td>
</tr>
</tbody>
</table>
<p>Database version number.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::query">
<code class="descname">query</code><span class="sig-paren">(</span><em>$sql</em><span class="optional">[</span>, <em>$binds = FALSE</em><span class="optional">[</span>, <em>$return_object = NULL</em><span class="optional">]</span><span class="optional">]</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::query" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$sql</strong> (<em>string</em>) – The SQL statement to execute</li>
<li><strong>$binds</strong> (<em>array</em>) – An array of binding data</li>
<li><strong>$return_object</strong> (<em>bool</em>) – Whether to return a result object or not</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">TRUE for successful “write-type” queries, CI_DB_result instance (method chaining) on “query” success, FALSE on failure</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">mixed</p>
</td>
</tr>
</tbody>
</table>
<p>Execute an SQL query.</p>
<p>Accepts an SQL string as input and returns a result object
upon successful execution of a “read” type query.</p>
<p>Returns:</p>
<blockquote>
<div><ul class="simple">
<li>Boolean TRUE upon successful execution of a “write type” queries</li>
<li>Boolean FALSE upon failure</li>
<li><code class="docutils literal"><span class="pre">CI_DB_result</span></code> object for “read type” queries</li>
</ul>
</div></blockquote>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::simple_query">
<code class="descname">simple_query</code><span class="sig-paren">(</span><em>$sql</em><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::simple_query" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$sql</strong> (<em>string</em>) – The SQL statement to execute</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">Whatever the underlying driver’s “query” function returns</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">mixed</p>
</td>
</tr>
</tbody>
</table>
<p>A simplified version of the <code class="docutils literal"><span class="pre">query()</span></code> method, appropriate
for use when you don’t need to get a result object or to
just send a query to the database and not care for the result.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::affected_rows">
<code class="descname">affected_rows</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::affected_rows" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Returns:</th><td class="field-body">Number of rows affected</td>
</tr>
<tr class="field-even field"><th class="field-name">Return type:</th><td class="field-body">int</td>
</tr>
</tbody>
</table>
<p>Returns the number of rows <em>changed</em> by the last executed query.</p>
<p>Useful for checking how much rows were created, updated or deleted
during the last executed query.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::trans_strict">
<code class="descname">trans_strict</code><span class="sig-paren">(</span><span class="optional">[</span><em>$mode = TRUE</em><span class="optional">]</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::trans_strict" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$mode</strong> (<em>bool</em>) – Strict mode flag</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">void</p>
</td>
</tr>
</tbody>
</table>
<p>Enable/disable transaction “strict” mode.</p>
<p>When strict mode is enabled, if you are running multiple
groups of transactions and one group fails, all subsequent
groups will be rolled back.</p>
<p>If strict mode is disabled, each group is treated
autonomously, meaning a failure of one group will not
affect any others.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::trans_off">
<code class="descname">trans_off</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::trans_off" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body">void</td>
</tr>
</tbody>
</table>
<p>Disables transactions at run-time.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::trans_start">
<code class="descname">trans_start</code><span class="sig-paren">(</span><span class="optional">[</span><em>$test_mode = FALSE</em><span class="optional">]</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::trans_start" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$test_mode</strong> (<em>bool</em>) – Test mode flag</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">TRUE on success, FALSE on failure</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">bool</p>
</td>
</tr>
</tbody>
</table>
<p>Start a transaction.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::trans_complete">
<code class="descname">trans_complete</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::trans_complete" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Returns:</th><td class="field-body">TRUE on success, FALSE on failure</td>
</tr>
<tr class="field-even field"><th class="field-name">Return type:</th><td class="field-body">bool</td>
</tr>
</tbody>
</table>
<p>Complete Transaction.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::trans_status">
<code class="descname">trans_status</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::trans_status" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Returns:</th><td class="field-body">TRUE if the transaction succeeded, FALSE if it failed</td>
</tr>
<tr class="field-even field"><th class="field-name">Return type:</th><td class="field-body">bool</td>
</tr>
</tbody>
</table>
<p>Lets you retrieve the transaction status flag to
determine if it has failed.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::compile_binds">
<code class="descname">compile_binds</code><span class="sig-paren">(</span><em>$sql</em>, <em>$binds</em><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::compile_binds" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$sql</strong> (<em>string</em>) – The SQL statement</li>
<li><strong>$binds</strong> (<em>array</em>) – An array of binding data</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">The updated SQL statement</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">string</p>
</td>
</tr>
</tbody>
</table>
<p>Compiles an SQL query with the bind values passed for it.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::is_write_type">
<code class="descname">is_write_type</code><span class="sig-paren">(</span><em>$sql</em><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::is_write_type" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$sql</strong> (<em>string</em>) – The SQL statement</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">TRUE if the SQL statement is of “write type”, FALSE if not</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">bool</p>
</td>
</tr>
</tbody>
</table>
<p>Determines if a query is of a “write” type (such as
INSERT, UPDATE, DELETE) or “read” type (i.e. SELECT).</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::elapsed_time">
<code class="descname">elapsed_time</code><span class="sig-paren">(</span><span class="optional">[</span><em>$decimals = 6</em><span class="optional">]</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::elapsed_time" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$decimals</strong> (<em>int</em>) – The number of decimal places</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">The aggregate query elapsed time, in microseconds</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">string</p>
</td>
</tr>
</tbody>
</table>
<p>Calculate the aggregate query elapsed time.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::total_queries">
<code class="descname">total_queries</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::total_queries" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Returns:</th><td class="field-body">The total number of queries executed</td>
</tr>
<tr class="field-even field"><th class="field-name">Return type:</th><td class="field-body">int</td>
</tr>
</tbody>
</table>
<p>Returns the total number of queries that have been
executed so far.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::last_query">
<code class="descname">last_query</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::last_query" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Returns:</th><td class="field-body">The last query executed</td>
</tr>
<tr class="field-even field"><th class="field-name">Return type:</th><td class="field-body">string</td>
</tr>
</tbody>
</table>
<p>Returns the last query that was executed.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::escape">
<code class="descname">escape</code><span class="sig-paren">(</span><em>$str</em><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::escape" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$str</strong> (<em>mixed</em>) – The value to escape, or an array of multiple ones</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">The escaped value(s)</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">mixed</p>
</td>
</tr>
</tbody>
</table>
<p>Escapes input data based on type, including boolean and
NULLs.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::escape_str">
<code class="descname">escape_str</code><span class="sig-paren">(</span><em>$str</em><span class="optional">[</span>, <em>$like = FALSE</em><span class="optional">]</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::escape_str" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$str</strong> (<em>mixed</em>) – A string value or array of multiple ones</li>
<li><strong>$like</strong> (<em>bool</em>) – Whether or not the string will be used in a LIKE condition</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">The escaped string(s)</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">mixed</p>
</td>
</tr>
</tbody>
</table>
<p>Escapes string values.</p>
<div class="admonition warning">
<p class="first admonition-title">Warning</p>
<p class="last">The returned strings do NOT include quotes
around them.</p>
</div>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::escape_like_str">
<code class="descname">escape_like_str</code><span class="sig-paren">(</span><em>$str</em><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::escape_like_str" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$str</strong> (<em>mixed</em>) – A string value or array of multiple ones</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">The escaped string(s)</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">mixed</p>
</td>
</tr>
</tbody>
</table>
<p>Escape LIKE strings.</p>
<p>Similar to <code class="docutils literal"><span class="pre">escape_str()</span></code>, but will also escape the <code class="docutils literal"><span class="pre">%</span></code>
and <code class="docutils literal"><span class="pre">_</span></code> wildcard characters, so that they don’t cause
false-positives in LIKE conditions.</p>
<div class="admonition important">
<p class="first admonition-title">Important</p>
<p class="last">The <code class="docutils literal"><span class="pre">escape_like_str()</span></code> method uses ‘!’ (exclamation mark)
to escape special characters for <em>LIKE</em> conditions. Because this
method escapes partial strings that you would wrap in quotes
yourself, it cannot automatically add the <code class="docutils literal"><span class="pre">ESCAPE</span> <span class="pre">'!'</span></code>
condition for you, and so you’ll have to manually do that.</p>
</div>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::primary">
<code class="descname">primary</code><span class="sig-paren">(</span><em>$table</em><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::primary" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$table</strong> (<em>string</em>) – Table name</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">The primary key name, FALSE if none</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">string</p>
</td>
</tr>
</tbody>
</table>
<p>Retrieves the primary key of a table.</p>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">If the database platform does not support primary
key detection, the first column name may be assumed
as the primary key.</p>
</div>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::count_all">
<code class="descname">count_all</code><span class="sig-paren">(</span><span class="optional">[</span><em>$table = ''</em><span class="optional">]</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::count_all" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$table</strong> (<em>string</em>) – Table name</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">Row count for the specified table</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">int</p>
</td>
</tr>
</tbody>
</table>
<p>Returns the total number of rows in a table, or 0 if no
table was provided.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::list_tables">
<code class="descname">list_tables</code><span class="sig-paren">(</span><span class="optional">[</span><em>$constrain_by_prefix = FALSE</em><span class="optional">]</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::list_tables" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$constrain_by_prefix</strong> (<em>bool</em>) – TRUE to match table names by the configured dbprefix</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">Array of table names or FALSE on failure</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">array</p>
</td>
</tr>
</tbody>
</table>
<p>Gets a list of the tables in the current database.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::table_exists">
<code class="descname">table_exists</code><span class="sig-paren">(</span><em>$table_name</em><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::table_exists" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$table_name</strong> (<em>string</em>) – The table name</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">TRUE if that table exists, FALSE if not</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">bool</p>
</td>
</tr>
</tbody>
</table>
<p>Determine if a particular table exists.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::list_fields">
<code class="descname">list_fields</code><span class="sig-paren">(</span><em>$table</em><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::list_fields" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$table</strong> (<em>string</em>) – The table name</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">Array of field names or FALSE on failure</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">array</p>
</td>
</tr>
</tbody>
</table>
<p>Gets a list of the field names in a table.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::field_exists">
<code class="descname">field_exists</code><span class="sig-paren">(</span><em>$field_name</em>, <em>$table_name</em><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::field_exists" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$table_name</strong> (<em>string</em>) – The table name</li>
<li><strong>$field_name</strong> (<em>string</em>) – The field name</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">TRUE if that field exists in that table, FALSE if not</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">bool</p>
</td>
</tr>
</tbody>
</table>
<p>Determine if a particular field exists.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::field_data">
<code class="descname">field_data</code><span class="sig-paren">(</span><em>$table</em><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::field_data" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$table</strong> (<em>string</em>) – The table name</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">Array of field data items or FALSE on failure</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">array</p>
</td>
</tr>
</tbody>
</table>
<p>Gets a list containing field data about a table.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::escape_identifiers">
<code class="descname">escape_identifiers</code><span class="sig-paren">(</span><em>$item</em><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::escape_identifiers" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$item</strong> (<em>mixed</em>) – The item or array of items to escape</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">The input item(s), escaped</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">mixed</p>
</td>
</tr>
</tbody>
</table>
<p>Escape SQL identifiers, such as column, table and names.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::insert_string">
<code class="descname">insert_string</code><span class="sig-paren">(</span><em>$table</em>, <em>$data</em><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::insert_string" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$table</strong> (<em>string</em>) – The target table</li>
<li><strong>$data</strong> (<em>array</em>) – An associative array of key/value pairs</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">The SQL INSERT statement, as a string</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">string</p>
</td>
</tr>
</tbody>
</table>
<p>Generate an INSERT statement string.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::update_string">
<code class="descname">update_string</code><span class="sig-paren">(</span><em>$table</em>, <em>$data</em>, <em>$where</em><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::update_string" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$table</strong> (<em>string</em>) – The target table</li>
<li><strong>$data</strong> (<em>array</em>) – An associative array of key/value pairs</li>
<li><strong>$where</strong> (<em>mixed</em>) – The WHERE statement conditions</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">The SQL UPDATE statement, as a string</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">string</p>
</td>
</tr>
</tbody>
</table>
<p>Generate an UPDATE statement string.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::call_function">
<code class="descname">call_function</code><span class="sig-paren">(</span><em>$function</em><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::call_function" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$function</strong> (<em>string</em>) – Function name</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">The function result</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">string</p>
</td>
</tr>
</tbody>
</table>
<p>Runs a native PHP function , using a platform agnostic
wrapper.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::cache_set_path">
<code class="descname">cache_set_path</code><span class="sig-paren">(</span><span class="optional">[</span><em>$path = ''</em><span class="optional">]</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::cache_set_path" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$path</strong> (<em>string</em>) – Path to the cache directory</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">void</p>
</td>
</tr>
</tbody>
</table>
<p>Sets the directory path to use for caching storage.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::cache_on">
<code class="descname">cache_on</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::cache_on" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Returns:</th><td class="field-body">TRUE if caching is on, FALSE if not</td>
</tr>
<tr class="field-even field"><th class="field-name">Return type:</th><td class="field-body">bool</td>
</tr>
</tbody>
</table>
<p>Enable database results caching.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::cache_off">
<code class="descname">cache_off</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::cache_off" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Returns:</th><td class="field-body">TRUE if caching is on, FALSE if not</td>
</tr>
<tr class="field-even field"><th class="field-name">Return type:</th><td class="field-body">bool</td>
</tr>
</tbody>
</table>
<p>Disable database results caching.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::cache_delete">
<code class="descname">cache_delete</code><span class="sig-paren">(</span><span class="optional">[</span><em>$segment_one = ''</em><span class="optional">[</span>, <em>$segment_two = ''</em><span class="optional">]</span><span class="optional">]</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::cache_delete" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$segment_one</strong> (<em>string</em>) – First URI segment</li>
<li><strong>$segment_two</strong> (<em>string</em>) – Second URI segment</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">TRUE on success, FALSE on failure</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">bool</p>
</td>
</tr>
</tbody>
</table>
<p>Delete the cache files associated with a particular URI.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::cache_delete_all">
<code class="descname">cache_delete_all</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::cache_delete_all" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Returns:</th><td class="field-body">TRUE on success, FALSE on failure</td>
</tr>
<tr class="field-even field"><th class="field-name">Return type:</th><td class="field-body">bool</td>
</tr>
</tbody>
</table>
<p>Delete all cache files.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::close">
<code class="descname">close</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::close" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body">void</td>
</tr>
</tbody>
</table>
<p>Close the DB Connection.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::display_error">
<code class="descname">display_error</code><span class="sig-paren">(</span><span class="optional">[</span><em>$error = ''</em><span class="optional">[</span>, <em>$swap = ''</em><span class="optional">[</span>, <em>$native = FALSE</em><span class="optional">]</span><span class="optional">]</span><span class="optional">]</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::display_error" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$error</strong> (<em>string</em>) – The error message</li>
<li><strong>$swap</strong> (<em>string</em>) – Any “swap” values</li>
<li><strong>$native</strong> (<em>bool</em>) – Whether to localize the message</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Return type:</th><td class="field-body"><p class="first">void</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">Displays the DB error screensends the application/views/errors/error_db.php template</p>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">string</p>
</td>
</tr>
</tbody>
</table>
<p>Display an error message and stop script execution.</p>
<p>The message is displayed using the
<em>application/views/errors/error_db.php</em> template.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_driver::protect_identifiers">
<code class="descname">protect_identifiers</code><span class="sig-paren">(</span><em>$item</em><span class="optional">[</span>, <em>$prefix_single = FALSE</em><span class="optional">[</span>, <em>$protect_identifiers = NULL</em><span class="optional">[</span>, <em>$field_exists = TRUE</em><span class="optional">]</span><span class="optional">]</span><span class="optional">]</span><span class="sig-paren">)</span><a class="headerlink" href="#CI_DB_driver::protect_identifiers" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$item</strong> (<em>string</em>) – The item to work with</li>
<li><strong>$prefix_single</strong> (<em>bool</em>) – Whether to apply the dbprefix even if the input item is a single identifier</li>
<li><strong>$protect_identifiers</strong> (<em>bool</em>) – Whether to quote identifiers</li>
<li><strong>$field_exists</strong> (<em>bool</em>) – Whether the supplied item contains a field name or not</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">The modified item</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">string</p>
</td>
</tr>
</tbody>
</table>
<p>Takes a column or table name (optionally with an alias)
and applies the configured <em>dbprefix</em> to it.</p>
<p>Some logic is necessary in order to deal with
column names that include the path.</p>
<p>Consider a query like this:</p>
<div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nx">SELECT</span> <span class="o">*</span> <span class="nx">FROM</span> <span class="nx">hostname</span><span class="o">.</span><span class="nx">database</span><span class="o">.</span><span class="nx">table</span><span class="o">.</span><span class="nx">column</span> <span class="k">AS</span> <span class="nx">c</span> <span class="nx">FROM</span> <span class="nx">hostname</span><span class="o">.</span><span class="nx">database</span><span class="o">.</span><span class="nx">table</span>
</pre></div>
</div>
<p>Or a query with aliasing:</p>
<div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nx">SELECT</span> <span class="nx">m</span><span class="o">.</span><span class="nx">member_id</span><span class="p">,</span> <span class="nx">m</span><span class="o">.</span><span class="nx">member_name</span> <span class="nx">FROM</span> <span class="nx">members</span> <span class="k">AS</span> <span class="nx">m</span>
</pre></div>
</div>
<p>Since the column name can include up to four segments
(host, DB, table, column) or also have an alias prefix,
we need to do a bit of work to figure this out and
insert the table prefix (if it exists) in the proper
position, and escape only the correct identifiers.</p>
<p>This method is used extensively by the Query Builder class.</p>
</dd></dl>

</dd></dl>

</div>


          </div>
          <footer>
  
    <div class="rst-footer-buttons" role="navigation" aria-label="footer navigation">
      
        <a href="../helpers/index.html" class="btn btn-neutral float-right" title="Helpers">Next <span class="fa fa-arrow-circle-right"></span></a>
      
      
        <a href="utilities.html" class="btn btn-neutral" title="Database Utility Class"><span class="fa fa-arrow-circle-left"></span> Previous</a>
      
    </div>
  

  <hr/>

  <div role="contentinfo">
    <p>
        &copy; Copyright 2014 - 2017, British Columbia Institute of Technology.
      Last updated on Sep 25, 2017.
    </p>
  </div>

  Built with <a href="http://sphinx-doc.org/">Sphinx</a> using a <a href="https://github.com/snide/sphinx_rtd_theme">theme</a> provided by <a href="https://readthedocs.org">Read the Docs</a>.
  
</footer>
        </div>
      </div>

    </section>

  </div>
  

    <script type="text/javascript">
        var DOCUMENTATION_OPTIONS = {
            URL_ROOT:'../',
            VERSION:'3.1.6',
            COLLAPSE_INDEX:false,
            FILE_SUFFIX:'.html',
            HAS_SOURCE:  false
        };
    </script>
      <script type="text/javascript" src="../_static/jquery.js"></script>
      <script type="text/javascript" src="../_static/underscore.js"></script>
      <script type="text/javascript" src="../_static/doctools.js"></script>

  
    <script type="text/javascript" src="../_static/js/theme.js"></script>
  

  <script type="text/javascript">
      jQuery(function () {
          SphinxRtdTheme.StickyNav.enable();
      });
  </script>
   

</body>
</html>