Skip to content

HTTPS clone URL

Subversion checkout URL

You can clone with HTTPS or Subversion.

Download ZIP
tree: 263479b5a3
Fetching contributors…

Cannot retrieve contributors at this time

663 lines (563 sloc) 24.087 kb
# oracle_adapter.rb -- ActiveRecord adapter for Oracle 8i, 9i, 10g
#
# Original author: Graham Jenkins
#
# Current maintainer: Michael Schoen <schoenm@earthlink.net>
#
#########################################################################
#
# Implementation notes:
# 1. Redefines (safely) a method in ActiveRecord to make it possible to
# implement an autonumbering solution for Oracle.
# 2. The OCI8 driver is patched to properly handle values for LONG and
# TIMESTAMP columns. The driver-author has indicated that a future
# release of the driver will obviate this patch.
# 3. LOB support is implemented through an after_save callback.
# 4. Oracle does not offer native LIMIT and OFFSET options; this
# functionality is mimiced through the use of nested selects.
# See http://asktom.oracle.com/pls/ask/f?p=4950:8:::::F4950_P8_DISPLAYID:127412348064
#
# Do what you want with this code, at your own peril, but if any
# significant portion of my code remains then please acknowledge my
# contribution.
# portions Copyright 2005 Graham Jenkins
require 'active_record/connection_adapters/abstract_adapter'
require 'delegate'
begin
require_library_or_gem 'oci8' unless self.class.const_defined? :OCI8
module ActiveRecord
class Base
def self.oracle_connection(config) #:nodoc:
# Use OCI8AutoRecover instead of normal OCI8 driver.
ConnectionAdapters::OracleAdapter.new OCI8AutoRecover.new(config), logger
end
# for backwards-compatibility
def self.oci_connection(config) #:nodoc:
config[:database] = config[:host]
self.oracle_connection(config)
end
# Enable the id column to be bound into the sql later, by the adapter's insert method.
# This is preferable to inserting the hard-coded value here, because the insert method
# needs to know the id value explicitly.
alias :attributes_with_quotes_pre_oracle :attributes_with_quotes #:nodoc:
def attributes_with_quotes(creating = true) #:nodoc:
aq = attributes_with_quotes_pre_oracle creating
if connection.class == ConnectionAdapters::OracleAdapter
aq[self.class.primary_key] = ":id" if creating && aq[self.class.primary_key].nil?
end
aq
end
# After setting large objects to empty, select the OCI8::LOB
# and write back the data.
after_save :write_lobs
def write_lobs() #:nodoc:
if connection.is_a?(ConnectionAdapters::OracleAdapter)
self.class.columns.select { |c| c.type == :binary }.each { |c|
value = self[c.name]
next if value.nil? || (value == '')
lob = connection.select_one(
"SELECT #{ c.name} FROM #{ self.class.table_name } WHERE #{ self.class.primary_key} = #{quote(id)}",
'Writable Large Object')[c.name]
lob.write value
}
end
end
private :write_lobs
end
module ConnectionAdapters #:nodoc:
class OracleColumn < Column #:nodoc:
attr_reader :sql_type
# overridden to add the concept of scale, required to differentiate
# between integer and float fields
def initialize(name, default, sql_type, limit, scale, null)
@name, @limit, @sql_type, @scale, @null = name, limit, sql_type, scale, null
@type = simplified_type(sql_type)
@default = type_cast(default)
@primary = nil
@text = [:string, :text].include? @type
@number = [:float, :integer].include? @type
end
def type_cast(value)
return nil if value.nil? || value =~ /^\s*null\s*$/i
case type
when :string then value
when :integer then defined?(value.to_i) ? value.to_i : (value ? 1 : 0)
when :float then value.to_f
when :datetime then cast_to_date_or_time(value)
when :time then cast_to_time(value)
else value
end
end
private
def simplified_type(field_type)
case field_type
when /char/i : :string
when /num|float|double|dec|real|int/i : @scale == 0 ? :integer : :float
when /date|time/i : @name =~ /_at$/ ? :time : :datetime
when /clob/i : :text
when /blob/i : :binary
end
end
def cast_to_date_or_time(value)
return value if value.is_a? Date
return nil if value.blank?
guess_date_or_time (value.is_a? Time) ? value : cast_to_time(value)
end
def cast_to_time(value)
return value if value.is_a? Time
time_array = ParseDate.parsedate value
time_array[0] ||= 2000; time_array[1] ||= 1; time_array[2] ||= 1;
Time.send(Base.default_timezone, *time_array) rescue nil
end
def guess_date_or_time(value)
(value.hour == 0 and value.min == 0 and value.sec == 0) ?
Date.new(value.year, value.month, value.day) : value
end
end
# This is an Oracle/OCI adapter for the ActiveRecord persistence
# framework. It relies upon the OCI8 driver, which works with Oracle 8i
# and above. Most recent development has been on Debian Linux against
# a 10g database, ActiveRecord 1.12.1 and OCI8 0.1.13.
# See: http://rubyforge.org/projects/ruby-oci8/
#
# Usage notes:
# * Key generation assumes a "${table_name}_seq" sequence is available
# for all tables; the sequence name can be changed using
# ActiveRecord::Base.set_sequence_name. When using Migrations, these
# sequences are created automatically.
# * Oracle uses DATE or TIMESTAMP datatypes for both dates and times.
# Consequently some hacks are employed to map data back to Date or Time
# in Ruby. If the column_name ends in _time it's created as a Ruby Time.
# Else if the hours/minutes/seconds are 0, I make it a Ruby Date. Else
# it's a Ruby Time. This is a bit nasty - but if you use Duck Typing
# you'll probably not care very much. In 9i and up it's tempting to
# map DATE to Date and TIMESTAMP to Time, but too many databases use
# DATE for both. Timezones and sub-second precision on timestamps are
# not supported.
# * Default values that are functions (such as "SYSDATE") are not
# supported. This is a restriction of the way ActiveRecord supports
# default values.
# * Support for Oracle8 is limited by Rails' use of ANSI join syntax, which
# is supported in Oracle9i and later. You will need to use #finder_sql for
# has_and_belongs_to_many associations to run against Oracle8.
#
# Required parameters:
#
# * <tt>:username</tt>
# * <tt>:password</tt>
# * <tt>:database</tt>
class OracleAdapter < AbstractAdapter
def adapter_name #:nodoc:
'Oracle'
end
def supports_migrations? #:nodoc:
true
end
def native_database_types #:nodoc
{
:primary_key => "NUMBER(38) NOT NULL PRIMARY KEY",
:string => { :name => "VARCHAR2", :limit => 255 },
:text => { :name => "CLOB" },
:integer => { :name => "NUMBER", :limit => 38 },
:float => { :name => "NUMBER" },
:datetime => { :name => "DATE" },
:timestamp => { :name => "DATE" },
:time => { :name => "DATE" },
:date => { :name => "DATE" },
:binary => { :name => "BLOB" },
:boolean => { :name => "NUMBER", :limit => 1 }
}
end
def table_alias_length
30
end
# QUOTING ==================================================
#
# see: abstract/quoting.rb
# camelCase column names need to be quoted; not that anyone using Oracle
# would really do this, but handling this case means we pass the test...
def quote_column_name(name) #:nodoc:
name =~ /[A-Z]/ ? "\"#{name}\"" : name
end
def quote_string(string) #:nodoc:
string.gsub(/'/, "''")
end
def quote(value, column = nil) #:nodoc:
if column and column.type == :binary then %Q{empty_#{ column.sql_type }()}
else case value
when String then %Q{'#{quote_string(value)}'}
when NilClass then 'null'
when TrueClass then '1'
when FalseClass then '0'
when Numeric then value.to_s
when Date, Time then %Q{'#{value.strftime("%Y-%m-%d %H:%M:%S")}'}
else %Q{'#{quote_string(value.to_yaml)}'}
end
end
end
# CONNECTION MANAGEMENT ====================================
#
# Returns true if the connection is active.
def active?
# Pings the connection to check if it's still good. Note that an
# #active? method is also available, but that simply returns the
# last known state, which isn't good enough if the connection has
# gone stale since the last use.
@connection.ping
rescue OCIException
false
end
# Reconnects to the database.
def reconnect!
@connection.reset!
rescue OCIException => e
@logger.warn "#{adapter_name} automatic reconnection failed: #{e.message}"
end
# Disconnects from the database.
def disconnect!
@connection.logoff rescue nil
@connection.active = false
end
# DATABASE STATEMENTS ======================================
#
# see: abstract/database_statements.rb
def select_all(sql, name = nil) #:nodoc:
select(sql, name)
end
def select_one(sql, name = nil) #:nodoc:
result = select_all(sql, name)
result.size > 0 ? result.first : nil
end
def execute(sql, name = nil) #:nodoc:
log(sql, name) { @connection.exec sql }
end
def insert(sql, name = nil, pk = nil, id_value = nil, sequence_name = nil) #:nodoc:
if pk.nil? # Who called us? What does the sql look like? No idea!
execute sql, name
elsif id_value # Pre-assigned id
log(sql, name) { @connection.exec sql }
else # Assume the sql contains a bind-variable for the id
id_value = select_one("select #{sequence_name}.nextval id from dual")['id']
log(sql, name) { @connection.exec sql, id_value }
end
id_value
end
alias :update :execute #:nodoc:
alias :delete :execute #:nodoc:
def begin_db_transaction #:nodoc:
@connection.autocommit = false
end
def commit_db_transaction #:nodoc:
@connection.commit
ensure
@connection.autocommit = true
end
def rollback_db_transaction #:nodoc:
@connection.rollback
ensure
@connection.autocommit = true
end
def add_limit_offset!(sql, options) #:nodoc:
offset = options[:offset] || 0
if limit = options[:limit]
sql.replace "select * from (select raw_sql_.*, rownum raw_rnum_ from (#{sql}) raw_sql_ where rownum <= #{offset+limit}) where raw_rnum_ > #{offset}"
elsif offset > 0
sql.replace "select * from (select raw_sql_.*, rownum raw_rnum_ from (#{sql}) raw_sql_) where raw_rnum_ > #{offset}"
end
end
def default_sequence_name(table, column) #:nodoc:
"#{table}_seq"
end
# SCHEMA STATEMENTS ========================================
#
# see: abstract/schema_statements.rb
def current_database #:nodoc:
select_one("select sys_context('userenv','db_name') db from dual")["db"]
end
def tables(name = nil) #:nodoc:
select_all("select lower(table_name) from user_tables").inject([]) do | tabs, t |
tabs << t.to_a.first.last
end
end
def indexes(table_name, name = nil) #:nodoc:
result = select_all(<<-SQL, name)
SELECT lower(i.index_name) as index_name, i.uniqueness, lower(c.column_name) as column_name
FROM user_indexes i, user_ind_columns c
WHERE i.table_name = '#{table_name.to_s.upcase}'
AND c.index_name = i.index_name
AND i.index_name NOT IN (SELECT index_name FROM user_constraints WHERE constraint_type = 'P')
ORDER BY i.index_name, c.column_position
SQL
current_index = nil
indexes = []
result.each do |row|
if current_index != row['index_name']
indexes << IndexDefinition.new(table_name, row['index_name'], row['uniqueness'] == "UNIQUE", [])
current_index = row['index_name']
end
indexes.last.columns << row['column_name']
end
indexes
end
def columns(table_name, name = nil) #:nodoc:
table_info = @connection.object_info(table_name)
table_cols = %Q{
select column_name, data_type, data_default, nullable,
decode(data_type, 'NUMBER', data_precision,
'VARCHAR2', data_length,
null) as length,
decode(data_type, 'NUMBER', data_scale, null) as scale
from all_tab_columns
where owner = '#{table_info.schema}'
and table_name = '#{table_info.name}'
order by column_id
}
select_all(table_cols, name).map do |row|
row['data_default'].sub!(/^'(.*)'\s*$/, '\1') if row['data_default']
OracleColumn.new(
oracle_downcase(row['column_name']),
row['data_default'],
row['data_type'],
(l = row['length']).nil? ? nil : l.to_i,
(s = row['scale']).nil? ? nil : s.to_i,
row['nullable'] == 'Y'
)
end
end
def create_table(name, options = {}) #:nodoc:
super(name, options)
execute "CREATE SEQUENCE #{name}_seq" unless options[:id] == false
end
def rename_table(name, new_name) #:nodoc:
execute "RENAME #{name} TO #{new_name}"
execute "RENAME #{name}_seq TO #{new_name}_seq" rescue nil
end
def drop_table(name) #:nodoc:
super(name)
execute "DROP SEQUENCE #{name}_seq" rescue nil
end
def remove_index(table_name, options = {}) #:nodoc:
execute "DROP INDEX #{index_name(table_name, options)}"
end
def change_column_default(table_name, column_name, default) #:nodoc:
execute "ALTER TABLE #{table_name} MODIFY #{column_name} DEFAULT #{quote(default)}"
end
def change_column(table_name, column_name, type, options = {}) #:nodoc:
change_column_sql = "ALTER TABLE #{table_name} MODIFY #{column_name} #{type_to_sql(type, options[:limit])}"
add_column_options!(change_column_sql, options)
execute(change_column_sql)
end
def rename_column(table_name, column_name, new_column_name) #:nodoc:
execute "ALTER TABLE #{table_name} RENAME COLUMN #{column_name} to #{new_column_name}"
end
def remove_column(table_name, column_name) #:nodoc:
execute "ALTER TABLE #{table_name} DROP COLUMN #{column_name}"
end
def structure_dump #:nodoc:
s = select_all("select sequence_name from user_sequences").inject("") do |structure, seq|
structure << "create sequence #{seq.to_a.first.last};\n\n"
end
select_all("select table_name from user_tables").inject(s) do |structure, table|
ddl = "create table #{table.to_a.first.last} (\n "
cols = select_all(%Q{
select column_name, data_type, data_length, data_precision, data_scale, data_default, nullable
from user_tab_columns
where table_name = '#{table.to_a.first.last}'
order by column_id
}).map do |row|
col = "#{row['column_name'].downcase} #{row['data_type'].downcase}"
if row['data_type'] =='NUMBER' and !row['data_precision'].nil?
col << "(#{row['data_precision'].to_i}"
col << ",#{row['data_scale'].to_i}" if !row['data_scale'].nil?
col << ')'
elsif row['data_type'].include?('CHAR')
col << "(#{row['data_length'].to_i})"
end
col << " default #{row['data_default']}" if !row['data_default'].nil?
col << ' not null' if row['nullable'] == 'N'
col
end
ddl << cols.join(",\n ")
ddl << ");\n\n"
structure << ddl
end
end
def structure_drop #:nodoc:
s = select_all("select sequence_name from user_sequences").inject("") do |drop, seq|
drop << "drop sequence #{seq.to_a.first.last};\n\n"
end
select_all("select table_name from user_tables").inject(s) do |drop, table|
drop << "drop table #{table.to_a.first.last} cascade constraints;\n\n"
end
end
private
def select(sql, name = nil)
cursor = log(sql, name) { @connection.exec sql }
cols = cursor.get_col_names.map { |x| oracle_downcase(x) }
rows = []
while row = cursor.fetch
hash = Hash.new
cols.each_with_index do |col, i|
hash[col] =
case row[i]
when OCI8::LOB
name == 'Writable Large Object' ? row[i]: row[i].read
when OraDate
(row[i].hour == 0 and row[i].minute == 0 and row[i].second == 0) ?
row[i].to_date : row[i].to_time
else row[i]
end unless col == 'raw_rnum_'
end
rows << hash
end
rows
ensure
cursor.close if cursor
end
# Oracle column names by default are case-insensitive, but treated as upcase;
# for neatness, we'll downcase within Rails. EXCEPT that folks CAN quote
# their column names when creating Oracle tables, which makes then case-sensitive.
# I don't know anybody who does this, but we'll handle the theoretical case of a
# camelCase column name. I imagine other dbs handle this different, since there's a
# unit test that's currently failing test_oci.
def oracle_downcase(column_name)
column_name =~ /[a-z]/ ? column_name : column_name.downcase
end
end
end
end
class OCI8 #:nodoc:
# This OCI8 patch may not longer be required with the upcoming
# release of version 0.2.
class Cursor #:nodoc:
alias :define_a_column_pre_ar :define_a_column
def define_a_column(i)
case do_ocicall(@ctx) { @parms[i - 1].attrGet(OCI_ATTR_DATA_TYPE) }
when 8 : @stmt.defineByPos(i, String, 65535) # Read LONG values
when 187 : @stmt.defineByPos(i, OraDate) # Read TIMESTAMP values
when 108
if @parms[i - 1].attrGet(OCI_ATTR_TYPE_NAME) == 'XMLTYPE'
@stmt.defineByPos(i, String, 65535)
else
raise 'unsupported datatype'
end
else define_a_column_pre_ar i
end
end
end
# missing constant from oci8 < 0.1.14
OCI_PTYPE_UNK = 0 unless defined?(OCI_PTYPE_UNK)
def object_info(name)
OraObject.new describe(name.to_s, OCI_PTYPE_UNK)
end
def describe(name, type)
@desc ||= @@env.alloc(OCIDescribe)
@desc.describeAny(@svc, name, type)
@desc.attrGet(OCI_ATTR_PARAM)
end
class OraObject
attr_reader :schema, :name
def initialize(info)
case info.attrGet(OCI_ATTR_PTYPE)
when OCI_PTYPE_TABLE, OCI_PTYPE_VIEW
@schema = info.attrGet(OCI_ATTR_OBJ_SCHEMA)
@name = info.attrGet(OCI_ATTR_OBJ_NAME)
when OCI_PTYPE_SYN
@schema = info.attrGet(OCI_ATTR_SCHEMA_NAME)
@name = info.attrGet(OCI_ATTR_NAME)
end
end
end
end
# The OracleConnectionFactory factors out the code necessary to connect and
# configure an Oracle/OCI connection.
class OracleConnectionFactory #:nodoc:
def new_connection(username, password, database)
conn = OCI8.new username, password, database
conn.exec %q{alter session set nls_date_format = 'YYYY-MM-DD HH24:MI:SS'}
conn.exec %q{alter session set nls_timestamp_format = 'YYYY-MM-DD HH24:MI:SS'} rescue nil
conn.autocommit = true
conn
end
end
# The OCI8AutoRecover class enhances the OCI8 driver with auto-recover and
# reset functionality. If a call to #exec fails, and autocommit is turned on
# (ie., we're not in the middle of a longer transaction), it will
# automatically reconnect and try again. If autocommit is turned off,
# this would be dangerous (as the earlier part of the implied transaction
# may have failed silently if the connection died) -- so instead the
# connection is marked as dead, to be reconnected on it's next use.
class OCI8AutoRecover < DelegateClass(OCI8) #:nodoc:
attr_accessor :active
alias :active? :active
cattr_accessor :auto_retry
class << self
alias :auto_retry? :auto_retry
end
@@auto_retry = false
def initialize(config, factory = OracleConnectionFactory.new)
@active = true
@username, @password, @database = config[:username], config[:password], config[:database]
@factory = factory
@connection = @factory.new_connection @username, @password, @database
super @connection
end
# Checks connection, returns true if active. Note that ping actively
# checks the connection, while #active? simply returns the last
# known state.
def ping
@connection.exec("select 1 from dual") { |r| nil }
@active = true
rescue
@active = false
raise
end
# Resets connection, by logging off and creating a new connection.
def reset!
logoff rescue nil
begin
@connection = @factory.new_connection @username, @password, @database
__setobj__ @connection
@active = true
rescue
@active = false
raise
end
end
# ORA-00028: your session has been killed
# ORA-01012: not logged on
# ORA-03113: end-of-file on communication channel
# ORA-03114: not connected to ORACLE
LOST_CONNECTION_ERROR_CODES = [ 28, 1012, 3113, 3114 ]
# Adds auto-recovery functionality.
#
# See: http://www.jiubao.org/ruby-oci8/api.en.html#label-11
def exec(sql, *bindvars)
should_retry = self.class.auto_retry? && autocommit?
begin
@connection.exec(sql, *bindvars)
rescue OCIException => e
raise unless LOST_CONNECTION_ERROR_CODES.include?(e.code)
@active = false
raise unless should_retry
should_retry = false
reset! rescue nil
retry
end
end
end
rescue LoadError
# OCI8 driver is unavailable.
module ActiveRecord # :nodoc:
class Base
def self.oracle_connection(config) # :nodoc:
# Set up a reasonable error message
raise LoadError, "Oracle/OCI libraries could not be loaded."
end
def self.oci_connection(config) # :nodoc:
# Set up a reasonable error message
raise LoadError, "Oracle/OCI libraries could not be loaded."
end
end
end
end
Jump to Line
Something went wrong with that request. Please try again.