diff --git a/src/MySql/AuditDiff.php b/src/MySql/AuditDiff.php
index 5c5f958..aed3794 100755
--- a/src/MySql/AuditDiff.php
+++ b/src/MySql/AuditDiff.php
@@ -293,7 +293,7 @@ private function resolveCanonicalAuditColumns()
   {
     if (empty($this->config['audit_columns']))
     {
-      $this->auditColumnsMetadata = new TableColumnsMetadata();
+      $this->auditColumnsMetadata = [];
     }
     else
     {
diff --git a/test/MySql/AbcFramework/AbcFrameworkTest.php b/test/MySql/AuditCommand/AbcFramework/AbcFrameworkTest.php
old mode 100644
new mode 100755
similarity index 99%
rename from test/MySql/AbcFramework/AbcFrameworkTest.php
rename to test/MySql/AuditCommand/AbcFramework/AbcFrameworkTest.php
index 760a33b..e3452f0
--- a/test/MySql/AbcFramework/AbcFrameworkTest.php
+++ b/test/MySql/AuditCommand/AbcFramework/AbcFrameworkTest.php
@@ -1,6 +1,6 @@
 <?php
 //----------------------------------------------------------------------------------------------------------------------
-namespace SetBased\Audit\Test\MySql\AbcFramework;
+namespace SetBased\Audit\Test\MySql\AbcFramework\AuditCommand;
 
 use SetBased\Audit\MySql\Command\AuditCommand;
 use SetBased\Audit\Test\MySql\AuditTestCase;
diff --git a/test/MySql/AbcFramework/config/audit.json b/test/MySql/AuditCommand/AbcFramework/config/audit.json
similarity index 100%
rename from test/MySql/AbcFramework/config/audit.json
rename to test/MySql/AuditCommand/AbcFramework/config/audit.json
diff --git a/test/MySql/AbcFramework/config/audit_metadata.json b/test/MySql/AuditCommand/AbcFramework/config/audit_metadata.json
similarity index 100%
rename from test/MySql/AbcFramework/config/audit_metadata.json
rename to test/MySql/AuditCommand/AbcFramework/config/audit_metadata.json
diff --git a/test/MySql/AbcFramework/config/setup.sql b/test/MySql/AuditCommand/AbcFramework/config/setup.sql
similarity index 100%
rename from test/MySql/AbcFramework/config/setup.sql
rename to test/MySql/AuditCommand/AbcFramework/config/setup.sql
diff --git a/test/MySql/AddColumn/AddColumnTest.php b/test/MySql/AuditCommand/AddColumn/AddColumnTest.php
old mode 100644
new mode 100755
similarity index 100%
rename from test/MySql/AddColumn/AddColumnTest.php
rename to test/MySql/AuditCommand/AddColumn/AddColumnTest.php
diff --git a/test/MySql/AddColumn/config/audit.json b/test/MySql/AuditCommand/AddColumn/config/audit.json
similarity index 100%
rename from test/MySql/AddColumn/config/audit.json
rename to test/MySql/AuditCommand/AddColumn/config/audit.json
diff --git a/test/MySql/AddColumn/config/audit_metadata.json b/test/MySql/AuditCommand/AddColumn/config/audit_metadata.json
similarity index 100%
rename from test/MySql/AddColumn/config/audit_metadata.json
rename to test/MySql/AuditCommand/AddColumn/config/audit_metadata.json
diff --git a/test/MySql/AddColumn/config/create_new_column.sql b/test/MySql/AuditCommand/AddColumn/config/create_new_column.sql
similarity index 100%
rename from test/MySql/AddColumn/config/create_new_column.sql
rename to test/MySql/AuditCommand/AddColumn/config/create_new_column.sql
diff --git a/test/MySql/AddColumn/config/setup.sql b/test/MySql/AuditCommand/AddColumn/config/setup.sql
similarity index 100%
rename from test/MySql/AddColumn/config/setup.sql
rename to test/MySql/AuditCommand/AddColumn/config/setup.sql
diff --git a/test/MySql/DropColumn/DropColumnTest.php b/test/MySql/AuditCommand/DropColumn/DropColumnTest.php
similarity index 100%
rename from test/MySql/DropColumn/DropColumnTest.php
rename to test/MySql/AuditCommand/DropColumn/DropColumnTest.php
diff --git a/test/MySql/DropColumn/config/audit.json b/test/MySql/AuditCommand/DropColumn/config/audit.json
similarity index 100%
rename from test/MySql/DropColumn/config/audit.json
rename to test/MySql/AuditCommand/DropColumn/config/audit.json
diff --git a/test/MySql/DropColumn/config/audit_metadata.json b/test/MySql/AuditCommand/DropColumn/config/audit_metadata.json
similarity index 100%
rename from test/MySql/DropColumn/config/audit_metadata.json
rename to test/MySql/AuditCommand/DropColumn/config/audit_metadata.json
diff --git a/test/MySql/DropColumn/config/drop_column.sql b/test/MySql/AuditCommand/DropColumn/config/drop_column.sql
similarity index 100%
rename from test/MySql/DropColumn/config/drop_column.sql
rename to test/MySql/AuditCommand/DropColumn/config/drop_column.sql
diff --git a/test/MySql/DropColumn/config/setup.sql b/test/MySql/AuditCommand/DropColumn/config/setup.sql
similarity index 100%
rename from test/MySql/DropColumn/config/setup.sql
rename to test/MySql/AuditCommand/DropColumn/config/setup.sql
diff --git a/test/MySql/LockTable/LockTableInnodbTest.php b/test/MySql/AuditCommand/LockTable/LockTableInnodbTest.php
old mode 100644
new mode 100755
similarity index 94%
rename from test/MySql/LockTable/LockTableInnodbTest.php
rename to test/MySql/AuditCommand/LockTable/LockTableInnodbTest.php
index 56975d5..d50ce70
--- a/test/MySql/LockTable/LockTableInnodbTest.php
+++ b/test/MySql/AuditCommand/LockTable/LockTableInnodbTest.php
@@ -1,6 +1,6 @@
 <?php
 //----------------------------------------------------------------------------------------------------------------------
-namespace SetBased\Audit\Test\MySql\LockTable;
+namespace SetBased\Audit\Test\MySql\AuditCommand\LockTable;
 
 use SetBased\Stratum\MySql\StaticDataLayer;
 
diff --git a/test/MySql/LockTable/LockTableMemoryTest.php b/test/MySql/AuditCommand/LockTable/LockTableMemoryTest.php
old mode 100644
new mode 100755
similarity index 94%
rename from test/MySql/LockTable/LockTableMemoryTest.php
rename to test/MySql/AuditCommand/LockTable/LockTableMemoryTest.php
index 9148a67..e87c3e4
--- a/test/MySql/LockTable/LockTableMemoryTest.php
+++ b/test/MySql/AuditCommand/LockTable/LockTableMemoryTest.php
@@ -1,6 +1,6 @@
 <?php
 //----------------------------------------------------------------------------------------------------------------------
-namespace SetBased\Audit\Test\MySql\LockTable;
+namespace SetBased\Audit\Test\MySql\AuditCommand\LockTable;
 
 use SetBased\Stratum\MySql\StaticDataLayer;
 
diff --git a/test/MySql/LockTable/LockTableMyisamTest.php b/test/MySql/AuditCommand/LockTable/LockTableMyisamTest.php
old mode 100644
new mode 100755
similarity index 94%
rename from test/MySql/LockTable/LockTableMyisamTest.php
rename to test/MySql/AuditCommand/LockTable/LockTableMyisamTest.php
index 0843150..c8d8eae
--- a/test/MySql/LockTable/LockTableMyisamTest.php
+++ b/test/MySql/AuditCommand/LockTable/LockTableMyisamTest.php
@@ -1,6 +1,6 @@
 <?php
 //----------------------------------------------------------------------------------------------------------------------
-namespace SetBased\Audit\Test\MySql\LockTable;
+namespace SetBased\Audit\Test\MySql\AuditCommand\LockTable;
 
 use SetBased\Stratum\MySql\StaticDataLayer;
 
diff --git a/test/MySql/LockTable/LockTableTestCase.php b/test/MySql/AuditCommand/LockTable/LockTableTestCase.php
old mode 100644
new mode 100755
similarity index 98%
rename from test/MySql/LockTable/LockTableTestCase.php
rename to test/MySql/AuditCommand/LockTable/LockTableTestCase.php
index 0f2668c..5397ae5
--- a/test/MySql/LockTable/LockTableTestCase.php
+++ b/test/MySql/AuditCommand/LockTable/LockTableTestCase.php
@@ -1,6 +1,6 @@
 <?php
 //----------------------------------------------------------------------------------------------------------------------
-namespace SetBased\Audit\Test\MySql\LockTable;
+namespace SetBased\Audit\Test\MySql\AuditCommand\LockTable;
 
 use SetBased\Audit\MySql\Command\AuditCommand;
 use SetBased\Audit\Test\MySql\AuditTestCase;
diff --git a/test/MySql/LockTable/config/audit.json b/test/MySql/AuditCommand/LockTable/config/audit.json
similarity index 100%
rename from test/MySql/LockTable/config/audit.json
rename to test/MySql/AuditCommand/LockTable/config/audit.json
diff --git a/test/MySql/LockTable/config/audit_metadata.json b/test/MySql/AuditCommand/LockTable/config/audit_metadata.json
similarity index 100%
rename from test/MySql/LockTable/config/audit_metadata.json
rename to test/MySql/AuditCommand/LockTable/config/audit_metadata.json
diff --git a/test/MySql/LockTable/config/generator.php b/test/MySql/AuditCommand/LockTable/config/generator.php
similarity index 92%
rename from test/MySql/LockTable/config/generator.php
rename to test/MySql/AuditCommand/LockTable/config/generator.php
index 49948e8..126cca3 100755
--- a/test/MySql/LockTable/config/generator.php
+++ b/test/MySql/AuditCommand/LockTable/config/generator.php
@@ -1,6 +1,7 @@
 #!/usr/bin/env php
 <?php
 //----------------------------------------------------------------------------------------------------------------------
+
 use SetBased\Affirm\ErrorHandler;
 use SetBased\Stratum\MySql\StaticDataLayer;
 
@@ -8,7 +9,8 @@
 $files = [__DIR__.'/../vendor/autoload.php',
           __DIR__.'/../../vendor/autoload.php',
           __DIR__.'/../../../vendor/autoload.php',
-          __DIR__.'/../../../../vendor/autoload.php'];
+          __DIR__.'/../../../../vendor/autoload.php',
+          __DIR__.'/../../../../../vendor/autoload.php'];
 
 foreach ($files as $file)
 {
diff --git a/test/MySql/LockTable/config/setup.sql b/test/MySql/AuditCommand/LockTable/config/setup.sql
similarity index 100%
rename from test/MySql/LockTable/config/setup.sql
rename to test/MySql/AuditCommand/LockTable/config/setup.sql
diff --git a/test/MySql/MinimalConfig/MinimalConfigTest.php b/test/MySql/AuditCommand/MinimalConfig/MinimalConfigTest.php
similarity index 100%
rename from test/MySql/MinimalConfig/MinimalConfigTest.php
rename to test/MySql/AuditCommand/MinimalConfig/MinimalConfigTest.php
diff --git a/test/MySql/MinimalConfig/config/audit.json b/test/MySql/AuditCommand/MinimalConfig/config/audit.json
similarity index 100%
rename from test/MySql/MinimalConfig/config/audit.json
rename to test/MySql/AuditCommand/MinimalConfig/config/audit.json
diff --git a/test/MySql/MinimalConfig/config/audit_metadata.json b/test/MySql/AuditCommand/MinimalConfig/config/audit_metadata.json
similarity index 100%
rename from test/MySql/MinimalConfig/config/audit_metadata.json
rename to test/MySql/AuditCommand/MinimalConfig/config/audit_metadata.json
diff --git a/test/MySql/MinimalConfig/config/setup.sql b/test/MySql/AuditCommand/MinimalConfig/config/setup.sql
similarity index 100%
rename from test/MySql/MinimalConfig/config/setup.sql
rename to test/MySql/AuditCommand/MinimalConfig/config/setup.sql
diff --git a/test/MySql/NewTable/NewTableTest.php b/test/MySql/AuditCommand/NewTable/NewTableTest.php
similarity index 100%
rename from test/MySql/NewTable/NewTableTest.php
rename to test/MySql/AuditCommand/NewTable/NewTableTest.php
diff --git a/test/MySql/NewTable/config/audit.json b/test/MySql/AuditCommand/NewTable/config/audit.json
similarity index 100%
rename from test/MySql/NewTable/config/audit.json
rename to test/MySql/AuditCommand/NewTable/config/audit.json
diff --git a/test/MySql/NewTable/config/audit_metadata.json b/test/MySql/AuditCommand/NewTable/config/audit_metadata.json
similarity index 100%
rename from test/MySql/NewTable/config/audit_metadata.json
rename to test/MySql/AuditCommand/NewTable/config/audit_metadata.json
diff --git a/test/MySql/NewTable/config/create_new_table.sql b/test/MySql/AuditCommand/NewTable/config/create_new_table.sql
similarity index 100%
rename from test/MySql/NewTable/config/create_new_table.sql
rename to test/MySql/AuditCommand/NewTable/config/create_new_table.sql
diff --git a/test/MySql/NewTable/config/setup.sql b/test/MySql/AuditCommand/NewTable/config/setup.sql
similarity index 100%
rename from test/MySql/NewTable/config/setup.sql
rename to test/MySql/AuditCommand/NewTable/config/setup.sql
diff --git a/test/MySql/RenameColumn/RenameColumnTest.php b/test/MySql/AuditCommand/RenameColumn/RenameColumnTest.php
similarity index 100%
rename from test/MySql/RenameColumn/RenameColumnTest.php
rename to test/MySql/AuditCommand/RenameColumn/RenameColumnTest.php
diff --git a/test/MySql/RenameColumn/config/audit.json b/test/MySql/AuditCommand/RenameColumn/config/audit.json
similarity index 100%
rename from test/MySql/RenameColumn/config/audit.json
rename to test/MySql/AuditCommand/RenameColumn/config/audit.json
diff --git a/test/MySql/RenameColumn/config/audit_metadata.json b/test/MySql/AuditCommand/RenameColumn/config/audit_metadata.json
similarity index 100%
rename from test/MySql/RenameColumn/config/audit_metadata.json
rename to test/MySql/AuditCommand/RenameColumn/config/audit_metadata.json
diff --git a/test/MySql/RenameColumn/config/rename_column.sql b/test/MySql/AuditCommand/RenameColumn/config/rename_column.sql
similarity index 100%
rename from test/MySql/RenameColumn/config/rename_column.sql
rename to test/MySql/AuditCommand/RenameColumn/config/rename_column.sql
diff --git a/test/MySql/RenameColumn/config/setup.sql b/test/MySql/AuditCommand/RenameColumn/config/setup.sql
similarity index 100%
rename from test/MySql/RenameColumn/config/setup.sql
rename to test/MySql/AuditCommand/RenameColumn/config/setup.sql
diff --git a/test/MySql/TableOptions/TableOptionsTest.php b/test/MySql/AuditCommand/TableOptions/TableOptionsTest.php
similarity index 100%
rename from test/MySql/TableOptions/TableOptionsTest.php
rename to test/MySql/AuditCommand/TableOptions/TableOptionsTest.php
diff --git a/test/MySql/TableOptions/config/audit.json b/test/MySql/AuditCommand/TableOptions/config/audit.json
similarity index 100%
rename from test/MySql/TableOptions/config/audit.json
rename to test/MySql/AuditCommand/TableOptions/config/audit.json
diff --git a/test/MySql/TableOptions/config/audit_metadata.json b/test/MySql/AuditCommand/TableOptions/config/audit_metadata.json
similarity index 100%
rename from test/MySql/TableOptions/config/audit_metadata.json
rename to test/MySql/AuditCommand/TableOptions/config/audit_metadata.json
diff --git a/test/MySql/TableOptions/config/setup.sql b/test/MySql/AuditCommand/TableOptions/config/setup.sql
similarity index 100%
rename from test/MySql/TableOptions/config/setup.sql
rename to test/MySql/AuditCommand/TableOptions/config/setup.sql
diff --git a/test/MySql/TriggerCode/TriggerCodeTest.php b/test/MySql/AuditCommand/TriggerCode/TriggerCodeTest.php
similarity index 100%
rename from test/MySql/TriggerCode/TriggerCodeTest.php
rename to test/MySql/AuditCommand/TriggerCode/TriggerCodeTest.php
diff --git a/test/MySql/DiffCommand/CharacterSetName/CharacterSetNameTest.php b/test/MySql/DiffCommand/CharacterSetName/CharacterSetNameTest.php
new file mode 100755
index 0000000..a37530d
--- /dev/null
+++ b/test/MySql/DiffCommand/CharacterSetName/CharacterSetNameTest.php
@@ -0,0 +1,90 @@
+<?php
+//----------------------------------------------------------------------------------------------------------------------
+namespace SetBased\Audit\Test\MySql\DiffCommand\CharacterSetName;
+
+use SetBased\Audit\MySql\AuditDataLayer;
+use SetBased\Audit\MySql\Command\AuditCommand;
+use SetBased\Audit\MySql\Command\DiffCommand;
+use SetBased\Audit\Test\MySql\AuditTestCase;
+use SetBased\Stratum\MySql\StaticDataLayer;
+use Symfony\Component\Console\Application;
+use Symfony\Component\Console\Tester\CommandTester;
+
+//----------------------------------------------------------------------------------------------------------------------
+/**
+ * Tests for running diff with a new table column in data table.
+ */
+class DiffCharacterSetNameTest extends AuditTestCase
+{
+  //--------------------------------------------------------------------------------------------------------------------
+  /**
+   * {@inheritdoc}
+   */
+  public static function setUpBeforeClass()
+  {
+    parent::setUpBeforeClass();
+
+    StaticDataLayer::disconnect();
+    StaticDataLayer::connect('localhost', 'test', 'test', self::$dataSchema);
+
+    StaticDataLayer::multiQuery(file_get_contents(__DIR__.'/config/setup.sql'));
+  }
+
+  //--------------------------------------------------------------------------------------------------------------------
+  public function test01()
+  {
+    // Run audit.
+    $this->runAudit();
+
+    // Create new column.
+    StaticDataLayer::multiQuery(file_get_contents(__DIR__.'/config/change_charset.sql'));
+
+    $this->runDiff();    
+  }
+
+  //--------------------------------------------------------------------------------------------------------------------
+  private function runDiff()
+  {
+    $application = new Application();
+    $application->add(new DiffCommand());
+
+    /** @var DiffCommand $command */
+    $command = $application->find('diff');
+    $command->setRewriteConfigFile(false);
+    $commandTester = new CommandTester($command);
+    $commandTester->execute(['command'     => $command->getName(),
+                             'config file' => __DIR__.'/config/audit.json']);
+
+    $output = $commandTester->getDisplay();
+    $this->assertContains('| c4     | varchar(20)              | varchar(20)                | int(11) |', $output, 'acquire');
+    $this->assertContains('|        | [utf8] [utf8_general_ci] | [ascii] [ascii_general_ci] |         |', $output, 'acquire');
+
+    // Reconnect to MySQL.
+    StaticDataLayer::disconnect();
+    StaticDataLayer::connect('localhost', 'test', 'test', self::$dataSchema);
+    AuditDataLayer::connect('localhost', 'test', 'test', self::$dataSchema);
+  }
+
+  //--------------------------------------------------------------------------------------------------------------------
+  private function runAudit()
+  {
+    $application = new Application();
+    $application->add(new AuditCommand());
+
+    /** @var AuditCommand $command */
+    $command = $application->find('audit');
+    $command->setRewriteConfigFile(true);
+    $commandTester = new CommandTester($command);
+    $commandTester->execute(['command'     => $command->getName(),
+                             'config file' => __DIR__.'/config/audit.json']);
+
+    // Reconnect to MySQL.
+    StaticDataLayer::disconnect();
+    StaticDataLayer::connect('localhost', 'test', 'test', self::$auditSchema);
+    AuditDataLayer::connect('localhost', 'test', 'test', self::$auditSchema);
+  }
+
+  //--------------------------------------------------------------------------------------------------------------------
+}
+
+//----------------------------------------------------------------------------------------------------------------------
diff --git a/test/MySql/DiffCommand/CharacterSetName/config/audit.json b/test/MySql/DiffCommand/CharacterSetName/config/audit.json
new file mode 100755
index 0000000..759435b
--- /dev/null
+++ b/test/MySql/DiffCommand/CharacterSetName/config/audit.json
@@ -0,0 +1,23 @@
+{
+    "database": {
+        "host": "localhost",
+        "user": "test",
+        "password": "test",
+        "data_schema": "test_data",
+        "audit_schema": "test_audit"
+    },
+    "metadata": "audit_metadata.json",
+    "tables": {
+        "TABLE1": {
+            "audit": true,
+            "skip": null,
+            "alias": "t1"
+        }
+    },
+    "audit_columns": [
+
+    ],
+    "additional_sql": [
+
+    ]
+}
\ No newline at end of file
diff --git a/test/MySql/DiffCommand/CharacterSetName/config/audit_metadata.json b/test/MySql/DiffCommand/CharacterSetName/config/audit_metadata.json
new file mode 100755
index 0000000..1b7cc90
--- /dev/null
+++ b/test/MySql/DiffCommand/CharacterSetName/config/audit_metadata.json
@@ -0,0 +1,19 @@
+{
+    "TABLE1": [
+        {
+            "column_name": "c1",
+            "column_type": "tinyint(4)",
+            "is_nullable": "YES"
+        },
+        {
+            "column_name": "c2",
+            "column_type": "smallint(6)",
+            "is_nullable": "YES"
+        },
+        {
+            "column_name": "c4",
+            "column_type": "int(11)",
+            "is_nullable": "YES"
+        }
+    ]
+}
\ No newline at end of file
diff --git a/test/MySql/DiffCommand/CharacterSetName/config/change_charset.sql b/test/MySql/DiffCommand/CharacterSetName/config/change_charset.sql
new file mode 100755
index 0000000..082fe07
--- /dev/null
+++ b/test/MySql/DiffCommand/CharacterSetName/config/change_charset.sql
@@ -0,0 +1 @@
+ALTER TABLE `TABLE1` MODIFY c4 VARCHAR(20) CHARACTER SET ascii;
\ No newline at end of file
diff --git a/test/MySql/DiffCommand/CharacterSetName/config/setup.sql b/test/MySql/DiffCommand/CharacterSetName/config/setup.sql
new file mode 100755
index 0000000..83d66af
--- /dev/null
+++ b/test/MySql/DiffCommand/CharacterSetName/config/setup.sql
@@ -0,0 +1,6 @@
+CREATE TABLE `TABLE1` (
+  c1 tinyint,
+  c2 smallint,
+  c4 varchar(20)
+);
+
diff --git a/test/MySql/DiffCommand/DiffTypeConfigAudit/DiffTypeConfigAuditTest.php b/test/MySql/DiffCommand/DiffTypeConfigAudit/DiffTypeConfigAuditTest.php
new file mode 100755
index 0000000..0fce190
--- /dev/null
+++ b/test/MySql/DiffCommand/DiffTypeConfigAudit/DiffTypeConfigAuditTest.php
@@ -0,0 +1,90 @@
+<?php
+//----------------------------------------------------------------------------------------------------------------------
+namespace SetBased\Audit\Test\MySql\DiffCommand\DiffTypeConfigAudit;
+
+use SetBased\Audit\MySql\AuditDataLayer;
+use SetBased\Audit\MySql\Command\AuditCommand;
+use SetBased\Audit\MySql\Command\DiffCommand;
+use SetBased\Audit\Test\MySql\AuditTestCase;
+use SetBased\Stratum\MySql\StaticDataLayer;
+use Symfony\Component\Console\Application;
+use Symfony\Component\Console\Tester\CommandTester;
+
+//----------------------------------------------------------------------------------------------------------------------
+/**
+ * Tests for running diff with a new table column in audit table.
+ */
+class DiffTypeConfigAuditTest extends AuditTestCase
+{
+  //--------------------------------------------------------------------------------------------------------------------
+  /**
+   * {@inheritdoc}
+   */
+  public static function setUpBeforeClass()
+  {
+    parent::setUpBeforeClass();
+
+    StaticDataLayer::disconnect();
+    StaticDataLayer::connect('localhost', 'test', 'test', self::$dataSchema);
+
+    StaticDataLayer::multiQuery(file_get_contents(__DIR__.'/config/setup.sql'));
+  }
+
+  //--------------------------------------------------------------------------------------------------------------------
+  public function test01()
+  {
+    // Run audit.
+    $this->runAudit();
+
+    // Create new column.
+    StaticDataLayer::multiQuery(file_get_contents(__DIR__.'/config/change_column_type.sql'));
+
+    $this->runDiff();    
+  }
+
+  //--------------------------------------------------------------------------------------------------------------------
+  private function runDiff()
+  {
+    $application = new Application();
+    $application->add(new DiffCommand());
+
+    /** @var DiffCommand $command */
+    $command = $application->find('diff');
+    $command->setRewriteConfigFile(false);
+    $commandTester = new CommandTester($command);
+    $commandTester->execute(['command'     => $command->getName(),
+                             'config file' => __DIR__.'/config/audit.json']);
+
+    $output = $commandTester->getDisplay();
+    $this->assertContains('| c4     | int(11)    | varchar(20)              | int(11) |', $output, 'acquire');
+    $this->assertContains('|        |            | [utf8] [utf8_general_ci] |         |', $output, 'acquire');
+
+    // Reconnect to MySQL.
+    StaticDataLayer::disconnect();
+    StaticDataLayer::connect('localhost', 'test', 'test', self::$dataSchema);
+    AuditDataLayer::connect('localhost', 'test', 'test', self::$dataSchema);
+  }
+
+  //--------------------------------------------------------------------------------------------------------------------
+  private function runAudit()
+  {
+    $application = new Application();
+    $application->add(new AuditCommand());
+
+    /** @var AuditCommand $command */
+    $command = $application->find('audit');
+    $command->setRewriteConfigFile(false);
+    $commandTester = new CommandTester($command);
+    $commandTester->execute(['command'     => $command->getName(),
+                             'config file' => __DIR__.'/config/audit.json']);
+
+    // Reconnect to MySQL.
+    StaticDataLayer::disconnect();
+    StaticDataLayer::connect('localhost', 'test', 'test', self::$auditSchema);
+    AuditDataLayer::connect('localhost', 'test', 'test', self::$auditSchema);
+  }
+
+  //--------------------------------------------------------------------------------------------------------------------
+}
+
+//----------------------------------------------------------------------------------------------------------------------
diff --git a/test/MySql/DiffCommand/DiffTypeConfigAudit/config/audit.json b/test/MySql/DiffCommand/DiffTypeConfigAudit/config/audit.json
new file mode 100755
index 0000000..759435b
--- /dev/null
+++ b/test/MySql/DiffCommand/DiffTypeConfigAudit/config/audit.json
@@ -0,0 +1,23 @@
+{
+    "database": {
+        "host": "localhost",
+        "user": "test",
+        "password": "test",
+        "data_schema": "test_data",
+        "audit_schema": "test_audit"
+    },
+    "metadata": "audit_metadata.json",
+    "tables": {
+        "TABLE1": {
+            "audit": true,
+            "skip": null,
+            "alias": "t1"
+        }
+    },
+    "audit_columns": [
+
+    ],
+    "additional_sql": [
+
+    ]
+}
\ No newline at end of file
diff --git a/test/MySql/DiffCommand/DiffTypeConfigAudit/config/audit_metadata.json b/test/MySql/DiffCommand/DiffTypeConfigAudit/config/audit_metadata.json
new file mode 100755
index 0000000..1b7cc90
--- /dev/null
+++ b/test/MySql/DiffCommand/DiffTypeConfigAudit/config/audit_metadata.json
@@ -0,0 +1,19 @@
+{
+    "TABLE1": [
+        {
+            "column_name": "c1",
+            "column_type": "tinyint(4)",
+            "is_nullable": "YES"
+        },
+        {
+            "column_name": "c2",
+            "column_type": "smallint(6)",
+            "is_nullable": "YES"
+        },
+        {
+            "column_name": "c4",
+            "column_type": "int(11)",
+            "is_nullable": "YES"
+        }
+    ]
+}
\ No newline at end of file
diff --git a/test/MySql/DiffCommand/DiffTypeConfigAudit/config/change_column_type.sql b/test/MySql/DiffCommand/DiffTypeConfigAudit/config/change_column_type.sql
new file mode 100755
index 0000000..9cab570
--- /dev/null
+++ b/test/MySql/DiffCommand/DiffTypeConfigAudit/config/change_column_type.sql
@@ -0,0 +1 @@
+ALTER TABLE `TABLE1` MODIFY c4 VARCHAR(20) CHARACTER SET utf8;
\ No newline at end of file
diff --git a/test/MySql/DiffCommand/DiffTypeConfigAudit/config/setup.sql b/test/MySql/DiffCommand/DiffTypeConfigAudit/config/setup.sql
new file mode 100755
index 0000000..efdd272
--- /dev/null
+++ b/test/MySql/DiffCommand/DiffTypeConfigAudit/config/setup.sql
@@ -0,0 +1,6 @@
+CREATE TABLE `TABLE1` (
+  c1 tinyint,
+  c2 smallint,
+  c4 int
+);
+
diff --git a/test/MySql/DiffCommand/NewColumnAuditTable/NewColumnAuditTableTest.php b/test/MySql/DiffCommand/NewColumnAuditTable/NewColumnAuditTableTest.php
new file mode 100755
index 0000000..9100382
--- /dev/null
+++ b/test/MySql/DiffCommand/NewColumnAuditTable/NewColumnAuditTableTest.php
@@ -0,0 +1,89 @@
+<?php
+//----------------------------------------------------------------------------------------------------------------------
+namespace SetBased\Audit\Test\MySql\DiffCommand\NewColumnAuditTableTest;
+
+use SetBased\Audit\MySql\AuditDataLayer;
+use SetBased\Audit\MySql\Command\AuditCommand;
+use SetBased\Audit\MySql\Command\DiffCommand;
+use SetBased\Audit\Test\MySql\AuditTestCase;
+use SetBased\Stratum\MySql\StaticDataLayer;
+use Symfony\Component\Console\Application;
+use Symfony\Component\Console\Tester\CommandTester;
+
+//----------------------------------------------------------------------------------------------------------------------
+/**
+ * Tests for running diff with a new table column in audit table.
+ */
+class NewColumnAuditTableTest extends AuditTestCase
+{
+  //--------------------------------------------------------------------------------------------------------------------
+  /**
+   * {@inheritdoc}
+   */
+  public static function setUpBeforeClass()
+  {
+    parent::setUpBeforeClass();
+
+    StaticDataLayer::disconnect();
+    StaticDataLayer::connect('localhost', 'test', 'test', self::$dataSchema);
+
+    StaticDataLayer::multiQuery(file_get_contents(__DIR__.'/config/setup.sql'));
+  }
+
+  //--------------------------------------------------------------------------------------------------------------------
+  public function test01()
+  {
+    // Run audit.
+    $this->runAudit();
+
+    // Create new column.
+    StaticDataLayer::multiQuery(file_get_contents(__DIR__.'/config/create_new_column.sql'));
+
+    $this->runDiff();    
+  }
+
+  //--------------------------------------------------------------------------------------------------------------------
+  private function runDiff()
+  {
+    $application = new Application();
+    $application->add(new DiffCommand());
+
+    /** @var DiffCommand $command */
+    $command = $application->find('diff');
+    $command->setRewriteConfigFile(false);
+    $commandTester = new CommandTester($command);
+    $commandTester->execute(['command'     => $command->getName(),
+                             'config file' => __DIR__.'/config/audit.json']);
+
+    $output = $commandTester->getDisplay();
+    $this->assertContains('| c3     | mediumint(9) |             |        |', $output, 'acquire');
+
+    // Reconnect to MySQL.
+    StaticDataLayer::disconnect();
+    StaticDataLayer::connect('localhost', 'test', 'test', self::$dataSchema);
+    AuditDataLayer::connect('localhost', 'test', 'test', self::$dataSchema);
+  }
+
+  //--------------------------------------------------------------------------------------------------------------------
+  private function runAudit()
+  {
+    $application = new Application();
+    $application->add(new AuditCommand());
+
+    /** @var AuditCommand $command */
+    $command = $application->find('audit');
+    $command->setRewriteConfigFile(true);
+    $commandTester = new CommandTester($command);
+    $commandTester->execute(['command'     => $command->getName(),
+                             'config file' => __DIR__.'/config/audit.json']);
+
+    // Reconnect to MySQL.
+    StaticDataLayer::disconnect();
+    StaticDataLayer::connect('localhost', 'test', 'test', self::$dataSchema);
+    AuditDataLayer::connect('localhost', 'test', 'test', self::$dataSchema);
+  }
+
+  //--------------------------------------------------------------------------------------------------------------------
+}
+
+//----------------------------------------------------------------------------------------------------------------------
diff --git a/test/MySql/DiffCommand/NewColumnAuditTable/config/audit.json b/test/MySql/DiffCommand/NewColumnAuditTable/config/audit.json
new file mode 100755
index 0000000..759435b
--- /dev/null
+++ b/test/MySql/DiffCommand/NewColumnAuditTable/config/audit.json
@@ -0,0 +1,23 @@
+{
+    "database": {
+        "host": "localhost",
+        "user": "test",
+        "password": "test",
+        "data_schema": "test_data",
+        "audit_schema": "test_audit"
+    },
+    "metadata": "audit_metadata.json",
+    "tables": {
+        "TABLE1": {
+            "audit": true,
+            "skip": null,
+            "alias": "t1"
+        }
+    },
+    "audit_columns": [
+
+    ],
+    "additional_sql": [
+
+    ]
+}
\ No newline at end of file
diff --git a/test/MySql/DiffCommand/NewColumnAuditTable/config/audit_metadata.json b/test/MySql/DiffCommand/NewColumnAuditTable/config/audit_metadata.json
new file mode 100755
index 0000000..1b7cc90
--- /dev/null
+++ b/test/MySql/DiffCommand/NewColumnAuditTable/config/audit_metadata.json
@@ -0,0 +1,19 @@
+{
+    "TABLE1": [
+        {
+            "column_name": "c1",
+            "column_type": "tinyint(4)",
+            "is_nullable": "YES"
+        },
+        {
+            "column_name": "c2",
+            "column_type": "smallint(6)",
+            "is_nullable": "YES"
+        },
+        {
+            "column_name": "c4",
+            "column_type": "int(11)",
+            "is_nullable": "YES"
+        }
+    ]
+}
\ No newline at end of file
diff --git a/test/MySql/DiffCommand/NewColumnAuditTable/config/create_new_column.sql b/test/MySql/DiffCommand/NewColumnAuditTable/config/create_new_column.sql
new file mode 100755
index 0000000..61142b8
--- /dev/null
+++ b/test/MySql/DiffCommand/NewColumnAuditTable/config/create_new_column.sql
@@ -0,0 +1 @@
+alter table `TABLE1` add column `c3` mediumint after `c2`;
\ No newline at end of file
diff --git a/test/MySql/DiffCommand/NewColumnAuditTable/config/setup.sql b/test/MySql/DiffCommand/NewColumnAuditTable/config/setup.sql
new file mode 100755
index 0000000..efdd272
--- /dev/null
+++ b/test/MySql/DiffCommand/NewColumnAuditTable/config/setup.sql
@@ -0,0 +1,6 @@
+CREATE TABLE `TABLE1` (
+  c1 tinyint,
+  c2 smallint,
+  c4 int
+);
+
diff --git a/test/MySql/DiffCommand/NewColumnDataTable/NewColumnDataTableTest.php b/test/MySql/DiffCommand/NewColumnDataTable/NewColumnDataTableTest.php
new file mode 100755
index 0000000..085a813
--- /dev/null
+++ b/test/MySql/DiffCommand/NewColumnDataTable/NewColumnDataTableTest.php
@@ -0,0 +1,89 @@
+<?php
+//----------------------------------------------------------------------------------------------------------------------
+namespace SetBased\Audit\Test\MySql\DiffCommand\NewColumnDataTableTest;
+
+use SetBased\Audit\MySql\AuditDataLayer;
+use SetBased\Audit\MySql\Command\AuditCommand;
+use SetBased\Audit\MySql\Command\DiffCommand;
+use SetBased\Audit\Test\MySql\AuditTestCase;
+use SetBased\Stratum\MySql\StaticDataLayer;
+use Symfony\Component\Console\Application;
+use Symfony\Component\Console\Tester\CommandTester;
+
+//----------------------------------------------------------------------------------------------------------------------
+/**
+ * Tests for running diff with a new table column in data table.
+ */
+class NewColumnDataTableTest extends AuditTestCase
+{
+  //--------------------------------------------------------------------------------------------------------------------
+  /**
+   * {@inheritdoc}
+   */
+  public static function setUpBeforeClass()
+  {
+    parent::setUpBeforeClass();
+
+    StaticDataLayer::disconnect();
+    StaticDataLayer::connect('localhost', 'test', 'test', self::$dataSchema);
+
+    StaticDataLayer::multiQuery(file_get_contents(__DIR__.'/config/setup.sql'));
+  }
+
+  //--------------------------------------------------------------------------------------------------------------------
+  public function test01()
+  {
+    // Run audit.
+    $this->runAudit();
+
+    // Create new column.
+    StaticDataLayer::multiQuery(file_get_contents(__DIR__.'/config/create_new_column.sql'));
+
+    $this->runDiff();    
+  }
+
+  //--------------------------------------------------------------------------------------------------------------------
+  private function runDiff()
+  {
+    $application = new Application();
+    $application->add(new DiffCommand());
+
+    /** @var DiffCommand $command */
+    $command = $application->find('diff');
+    $command->setRewriteConfigFile(false);
+    $commandTester = new CommandTester($command);
+    $commandTester->execute(['command'     => $command->getName(),
+                             'config file' => __DIR__.'/config/audit.json']);
+
+    $output = $commandTester->getDisplay();
+    $this->assertContains('| c3     |            | mediumint(9) |        |', $output, 'acquire');
+
+    // Reconnect to MySQL.
+    StaticDataLayer::disconnect();
+    StaticDataLayer::connect('localhost', 'test', 'test', self::$dataSchema);
+    AuditDataLayer::connect('localhost', 'test', 'test', self::$dataSchema);
+  }
+
+  //--------------------------------------------------------------------------------------------------------------------
+  private function runAudit()
+  {
+    $application = new Application();
+    $application->add(new AuditCommand());
+
+    /** @var AuditCommand $command */
+    $command = $application->find('audit');
+    $command->setRewriteConfigFile(true);
+    $commandTester = new CommandTester($command);
+    $commandTester->execute(['command'     => $command->getName(),
+                             'config file' => __DIR__.'/config/audit.json']);
+
+    // Reconnect to MySQL.
+    StaticDataLayer::disconnect();
+    StaticDataLayer::connect('localhost', 'test', 'test', self::$auditSchema);
+    AuditDataLayer::connect('localhost', 'test', 'test', self::$auditSchema);
+  }
+
+  //--------------------------------------------------------------------------------------------------------------------
+}
+
+//----------------------------------------------------------------------------------------------------------------------
diff --git a/test/MySql/DiffCommand/NewColumnDataTable/config/audit.json b/test/MySql/DiffCommand/NewColumnDataTable/config/audit.json
new file mode 100644
index 0000000..759435b
--- /dev/null
+++ b/test/MySql/DiffCommand/NewColumnDataTable/config/audit.json
@@ -0,0 +1,23 @@
+{
+    "database": {
+        "host": "localhost",
+        "user": "test",
+        "password": "test",
+        "data_schema": "test_data",
+        "audit_schema": "test_audit"
+    },
+    "metadata": "audit_metadata.json",
+    "tables": {
+        "TABLE1": {
+            "audit": true,
+            "skip": null,
+            "alias": "t1"
+        }
+    },
+    "audit_columns": [
+
+    ],
+    "additional_sql": [
+
+    ]
+}
\ No newline at end of file
diff --git a/test/MySql/DiffCommand/NewColumnDataTable/config/audit_metadata.json b/test/MySql/DiffCommand/NewColumnDataTable/config/audit_metadata.json
new file mode 100644
index 0000000..1b7cc90
--- /dev/null
+++ b/test/MySql/DiffCommand/NewColumnDataTable/config/audit_metadata.json
@@ -0,0 +1,19 @@
+{
+    "TABLE1": [
+        {
+            "column_name": "c1",
+            "column_type": "tinyint(4)",
+            "is_nullable": "YES"
+        },
+        {
+            "column_name": "c2",
+            "column_type": "smallint(6)",
+            "is_nullable": "YES"
+        },
+        {
+            "column_name": "c4",
+            "column_type": "int(11)",
+            "is_nullable": "YES"
+        }
+    ]
+}
\ No newline at end of file
diff --git a/test/MySql/DiffCommand/NewColumnDataTable/config/create_new_column.sql b/test/MySql/DiffCommand/NewColumnDataTable/config/create_new_column.sql
new file mode 100755
index 0000000..61142b8
--- /dev/null
+++ b/test/MySql/DiffCommand/NewColumnDataTable/config/create_new_column.sql
@@ -0,0 +1 @@
+alter table `TABLE1` add column `c3` mediumint after `c2`;
\ No newline at end of file
diff --git a/test/MySql/DiffCommand/NewColumnDataTable/config/setup.sql b/test/MySql/DiffCommand/NewColumnDataTable/config/setup.sql
new file mode 100755
index 0000000..efdd272
--- /dev/null
+++ b/test/MySql/DiffCommand/NewColumnDataTable/config/setup.sql
@@ -0,0 +1,6 @@
+CREATE TABLE `TABLE1` (
+  c1 tinyint,
+  c2 smallint,
+  c4 int
+);
+