Class: ActiveRecord::ConnectionAdapters::OracleEnhancedAdapter

Inherits:
AbstractAdapter
  • Object
show all
Includes:
ActiveRecord::ConnectionAdapters::OracleEnhanced::ContextIndex, ActiveRecord::ConnectionAdapters::OracleEnhanced::DatabaseLimits, ActiveRecord::ConnectionAdapters::OracleEnhanced::DatabaseStatements, ActiveRecord::ConnectionAdapters::OracleEnhanced::DbmsOutput, ActiveRecord::ConnectionAdapters::OracleEnhanced::Quoting, ActiveRecord::ConnectionAdapters::OracleEnhanced::SchemaStatements, ActiveRecord::ConnectionAdapters::OracleEnhanced::StructureDump
Defined in:
lib/active_record/connection_adapters/oracle_enhanced_adapter.rb,
lib/active_record/connection_adapters/oracle_enhanced/database_tasks.rb

Overview

Oracle enhanced adapter will work with both CRuby ruby-oci8 gem (which provides interface to Oracle OCI client) or with JRuby and Oracle JDBC driver.

It should work with Oracle 10g, 11g and 12c databases.

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. Use set_sequence_name :autogenerated with legacy tables that have triggers that populate primary keys 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. 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.

Required parameters:

  • :username

  • :password

  • :database - either TNS alias or connection string for OCI client or database name in JDBC connection string

Optional parameters:

  • :host - host name for JDBC connection, defaults to “localhost”

  • :port - port number for JDBC connection, defaults to 1521

  • :privilege - set “SYSDBA” if you want to connect with this privilege

  • :allow_concurrency - set to “true” if non-blocking mode should be enabled (just for OCI client)

  • :prefetch_rows - how many rows should be fetched at one time to increase performance, defaults to 100

  • :cursor_sharing - cursor sharing mode to minimize amount of unique statements, no default value

  • :time_zone - database session time zone (it is recommended to set it using ENV which will be then also used for database session time zone)

  • :schema - database schema which holds schema objects.

  • :tcp_keepalive - TCP keepalive is enabled for OCI client, defaults to true

  • :tcp_keepalive_time - TCP keepalive time for OCI client, defaults to 600

Optionals NLS parameters:

  • :nls_calendar

  • :nls_comp

  • :nls_currency

  • :nls_date_language

  • :nls_dual_currency

  • :nls_iso_currency

  • :nls_language

  • :nls_length_semantics - semantics of size of VARCHAR2 and CHAR columns, defaults to CHAR (meaning that size specifies number of characters and not bytes)

  • :nls_nchar_conv_excp

  • :nls_numeric_characters

  • :nls_sort

  • :nls_territory

  • :nls_timestamp_tz_format

  • :nls_time_format

  • :nls_time_tz_format

Fixed NLS values (not overridable):

  • :nls_date_format - format for :date columns is YYYY-MM-DD HH24:MI:SS

  • :nls_timestamp_format - format for :timestamp columns is YYYY-MM-DD HH24:MI:SS:FF6

Direct Known Subclasses

OracleAdapter

Defined Under Namespace

Classes: DatabaseTasks, StatementPool

Constant Summary collapse

ADAPTER_NAME = 
"OracleEnhanced"
DEFAULT_NLS_PARAMETERS =

:stopdoc:

{
  nls_calendar: nil,
  nls_comp: nil,
  nls_currency: nil,
  nls_date_language: nil,
  nls_dual_currency: nil,
  nls_iso_currency: nil,
  nls_language: nil,
  nls_length_semantics: "CHAR",
  nls_nchar_conv_excp: nil,
  nls_numeric_characters: nil,
  nls_sort: nil,
  nls_territory: nil,
  nls_timestamp_tz_format: nil,
  nls_time_format: nil,
  nls_time_tz_format: nil
}
FIXED_NLS_PARAMETERS =

:stopdoc:

{
  nls_date_format: "YYYY-MM-DD HH24:MI:SS",
  nls_timestamp_format: "YYYY-MM-DD HH24:MI:SS:FF6"
}
NATIVE_DATABASE_TYPES =

:stopdoc:

{
  primary_key: "NUMBER(38) NOT NULL PRIMARY KEY",
  string: { name: "VARCHAR2", limit: 255 },
  text: { name: "CLOB" },
  ntext: { name: "NCLOB" },
  integer: { name: "NUMBER", limit: 38 },
  float: { name: "BINARY_FLOAT" },
  decimal: { name: "NUMBER" },
  datetime: { name: "TIMESTAMP" },
  timestamp: { name: "TIMESTAMP" },
  timestamptz: { name: "TIMESTAMP WITH TIME ZONE" },
  timestampltz: { name: "TIMESTAMP WITH LOCAL TIME ZONE" },
  time: { name: "TIMESTAMP" },
  date: { name: "DATE" },
  binary: { name: "BLOB" },
  boolean: { name: "NUMBER", limit: 1 },
  raw: { name: "RAW", limit: 2000 },
  bigint: { name: "NUMBER", limit: 19 }
}
NATIVE_DATABASE_TYPES_BOOLEAN_STRINGS =

if emulate_booleans_from_strings then store booleans in VARCHAR2

NATIVE_DATABASE_TYPES.dup.merge(
  boolean: { name: "VARCHAR2", limit: 1 }
)
AUTOGENERATED_SEQUENCE_NAME =

use in set_sequence_name to avoid fetching primary key value from sequence

"autogenerated"
VERSION = 
File.read(File.expand_path("../../../../../VERSION", __FILE__)).chomp

Constants included from ActiveRecord::ConnectionAdapters::OracleEnhanced::StructureDump

ActiveRecord::ConnectionAdapters::OracleEnhanced::StructureDump::STATEMENT_TOKEN

Constants included from ActiveRecord::ConnectionAdapters::OracleEnhanced::DbmsOutput

ActiveRecord::ConnectionAdapters::OracleEnhanced::DbmsOutput::DBMS_OUTPUT_BUFFER_SIZE

Constants included from ActiveRecord::ConnectionAdapters::OracleEnhanced::DatabaseLimits

ActiveRecord::ConnectionAdapters::OracleEnhanced::DatabaseLimits::IDENTIFIER_MAX_LENGTH

Constants included from ActiveRecord::ConnectionAdapters::OracleEnhanced::Quoting

ActiveRecord::ConnectionAdapters::OracleEnhanced::Quoting::NONQUOTED_OBJECT_NAME, ActiveRecord::ConnectionAdapters::OracleEnhanced::Quoting::VALID_TABLE_NAME

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Methods included from ActiveRecord::ConnectionAdapters::OracleEnhanced::StructureDump

#execute_structure_dump, #foreign_key_definition, #full_drop, #structure_drop, #structure_dump, #structure_dump_column, #structure_dump_column_comments, #structure_dump_db_stored_code, #structure_dump_fk_constraints, #structure_dump_indexes, #structure_dump_primary_key, #structure_dump_synonyms, #structure_dump_table_comments, #structure_dump_unique_keys, #structure_dump_views, #structure_dump_virtual_column, #temp_table_drop

Methods included from ActiveRecord::ConnectionAdapters::OracleEnhanced::DbmsOutput

#dbms_output_enabled?, #disable_dbms_output, #enable_dbms_output

Methods included from ActiveRecord::ConnectionAdapters::OracleEnhanced::DatabaseLimits

#column_name_length, #in_clause_length, #sequence_name_length, #table_name_length

Methods included from ActiveRecord::ConnectionAdapters::OracleEnhanced::Quoting

#_quote, #_type_cast, #column_name_matcher, #column_name_with_order_matcher, mixed_case?, #quote_column_name, #quote_column_name_or_expression, #quote_string, #quote_table_name, #quoted_false, #quoted_true, #unquoted_false, #unquoted_true, valid_table_name?

Methods included from ActiveRecord::ConnectionAdapters::OracleEnhanced::OCIQuoting

#_type_cast

Methods included from ActiveRecord::ConnectionAdapters::OracleEnhanced::JDBCQuoting

#_type_cast

Methods included from ActiveRecord::ConnectionAdapters::OracleEnhanced::ContextIndex

#add_context_index, #remove_context_index

Methods included from ActiveRecord::ConnectionAdapters::OracleEnhanced::SchemaStatements

#add_column, #add_index, #add_index_options, #add_reference, #add_synonym, #aliased_types, #change_column, #change_column_comment, #change_column_default, #change_column_null, #change_table_comment, #column_comment, #columns, #create_alter_table, #create_schema_dumper, #create_table, #data_source_exists?, #data_sources, #disable_referential_integrity, #drop_table, #extract_foreign_key_action, #foreign_keys, #index_name, #index_name_exists?, #indexes, #insert_versions_sql, #materialized_views, #remove_column, #remove_index, #remove_synonym, #rename_column, #rename_index, #rename_table, #synonyms, #table_comment, #table_exists?, #table_options, #tables, #tablespace, #type_to_sql, #update_table_definition, #views

Methods included from ActiveRecord::ConnectionAdapters::OracleEnhanced::DatabaseStatements

#begin_db_transaction, #begin_isolated_db_transaction, #clear_cache!, #commit_db_transaction, #create_savepoint, #default_sequence_name, #empty_insert_statement_value, #exec_insert, #exec_query, #exec_rollback_db_transaction, #exec_rollback_to_savepoint, #exec_update, #execute, #explain, #insert, #insert_fixture, #insert_fixtures_set, #release_savepoint, #sql_for_insert, #supports_explain?, #transaction_isolation_levels, #write_lobs

Constructor Details

#initialize(connection, logger = nil, config = {}) ⇒ OracleEnhancedAdapter

:nodoc:



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 242

def initialize(connection, logger = nil, config = {}) # :nodoc:
  super(connection, logger, config)
  @enable_dbms_output = false
  @do_not_prefetch_primary_key = {}
  @columns_cache = {}
end

Instance Attribute Details

#auto_retry ⇒ Object

If SQL statement fails due to lost connection then reconnect and retry SQL statement if autocommit mode is enabled. By default this functionality is disabled.



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 423

def auto_retry
  @auto_retry
end

Class Method Details

.database_exists?(config) ⇒ Boolean

Oracle enhanced adapter has no implementation because Oracle Database cannot detect `NoDatabaseError`. Please refer to the following discussion for details. github.com/rsim/oracle-enhanced/pull/1900

Returns:

  • (Boolean)

Raises:

  • (NotImplementedError) 


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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 259

def self.database_exists?(config)
  raise NotImplementedError
end

Instance Method Details

#active? ⇒ Boolean

Returns true if the connection is active.

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 437

def active? #:nodoc:
  # 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 OracleEnhanced::ConnectionException
  false
end

#adapter_name ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 251

def adapter_name #:nodoc:
  ADAPTER_NAME
end

#arel_visitor ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 263

def arel_visitor # :nodoc:
  if supports_fetch_first_n_rows_and_offset?
    Arel::Visitors::Oracle12.new(self)
  else
    Arel::Visitors::Oracle.new(self)
  end
end

#build_statement_pool ⇒ Object 



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 271

def build_statement_pool
  StatementPool.new(self.class.type_cast_config_to_integer(@config[:statement_limit]))
end

#check_version ⇒ Object 



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 684

def check_version
  version = get_database_version.join(".").to_f

  if version < 10
    raise "Your version of Oracle (#{version}) is too old. Active Record Oracle enhanced adapter supports Oracle >= 10g."
  end
end

#clear_table_columns_cache(table_name) ⇒ Object 



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 587

def clear_table_columns_cache(table_name)
  @columns_cache[table_name.to_s] = nil
end

#column_definitions(table_name) ⇒ Object 



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 561

def column_definitions(table_name)
  (owner, desc_table_name) = @connection.describe(table_name)

  select_all(<<~SQL.squish, "SCHEMA")
    SELECT /*+ OPTIMIZER_FEATURES_ENABLE('11.2.0.2') */ cols.column_name AS name, cols.data_type AS sql_type,
           cols.data_default, cols.nullable, cols.virtual_column, cols.hidden_column,
           cols.data_type_owner AS sql_type_owner,
           DECODE(cols.data_type, 'NUMBER', data_precision,
                             'FLOAT', data_precision,
                             'VARCHAR2', DECODE(char_used, 'C', char_length, data_length),
                             'RAW', DECODE(char_used, 'C', char_length, data_length),
                             'CHAR', DECODE(char_used, 'C', char_length, data_length),
                              NULL) AS limit,
           DECODE(data_type, 'NUMBER', data_scale, NULL) AS scale,
           comments.comments as column_comment
      FROM all_tab_cols cols, all_col_comments comments
     WHERE cols.owner      = '#{owner}'
       AND cols.table_name = #{quote(desc_table_name)}
       AND cols.hidden_column = 'NO'
       AND cols.owner = comments.owner
       AND cols.table_name = comments.table_name
       AND cols.column_name = comments.column_name
     ORDER BY cols.column_id
  SQL
end

#columns_for_distinct(columns, orders) ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 651

def columns_for_distinct(columns, orders) #:nodoc:
  # construct a valid columns name for DISTINCT clause,
  # ie. one that includes the ORDER BY columns, using FIRST_VALUE such that
  # the inclusion of these columns doesn't invalidate the DISTINCT
  #
  # It does not construct DISTINCT clause. Just return column names for distinct.
  order_columns = orders.reject(&:blank?).map { |s|
      s = visitor.compile(s) unless s.is_a?(String)
      # remove any ASC/DESC modifiers
      s.gsub(/\s+(ASC|DESC)\s*?/i, "")
    }.reject(&:blank?).map.with_index { |column, i|
      "FIRST_VALUE(#{column}) OVER (PARTITION BY #{columns} ORDER BY #{column}) AS alias_#{i}__"
    }
  (order_columns << super).join(", ")
end

#current_database ⇒ Object

Current database name



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 529

def current_database
  select_value(<<~SQL.squish, "SCHEMA")
    SELECT SYS_CONTEXT('userenv', 'con_name') FROM dual
  SQL
rescue ActiveRecord::StatementInvalid
  select_value(<<~SQL.squish, "SCHEMA")
    SELECT SYS_CONTEXT('userenv', 'db_name') FROM dual
  SQL
end

#current_schema ⇒ Object

Current database session schema



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 547

def current_schema
  select_value(<<~SQL.squish, "SCHEMA")
    SELECT SYS_CONTEXT('userenv', 'current_schema') FROM dual
  SQL
end

#current_user ⇒ Object

Current database session user



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 540

def current_user
  select_value(<<~SQL.squish, "SCHEMA")
    SELECT SYS_CONTEXT('userenv', 'session_user') FROM dual
  SQL
end

#default_sequence_start_value ⇒ Object

:singleton-method: Specify default sequence start with value (by default 1 if not explicitly set), e.g.:

ActiveRecord::ConnectionAdapters::OracleEnhancedAdapter.default_sequence_start_value = 10000



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 205

cattr_accessor :default_sequence_start_value

#default_tablespace ⇒ Object

Default tablespace name of current user



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 554

def default_tablespace
  select_value(<<~SQL.squish, "SCHEMA")
    SELECT /*+ OPTIMIZER_FEATURES_ENABLE('11.2.0.2') */ LOWER(default_tablespace) FROM user_users
    WHERE username = SYS_CONTEXT('userenv', 'current_schema')
  SQL
end

#default_tablespaces ⇒ Object

:singleton-method: OracleEnhancedAdapter will use the default tablespace, but if you want specific types of objects to go into specific tablespaces, specify them like this in an initializer:

 ActiveRecord::ConnectionAdapters::OracleEnhancedAdapter.default_tablespaces =
{:clob => 'TS_LOB', :blob => 'TS_LOB', :index => 'TS_INDEX', :table => 'TS_DATA'}

Using the :tablespace option where available (e.g create_table) will take precedence over these settings.



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 177

cattr_accessor :default_tablespaces

#discard! ⇒ Object 



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 466

def discard!
  super
  @connection = nil
end

#disconnect! ⇒ Object

Disconnects from the database.



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 461

def disconnect! #:nodoc:
  super
  @connection.logoff rescue nil
end

#emulate_booleans ⇒ Object

:singleton-method: By default, the OracleEnhancedAdapter will consider all columns of type NUMBER(1) as boolean. If you wish to disable this emulation you can add the following line to your initializer file:

ActiveRecord::ConnectionAdapters::OracleEnhancedAdapter.emulate_booleans = false



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 164

cattr_accessor :emulate_booleans

#emulate_booleans_from_strings ⇒ Object

:singleton-method: If you wish that CHAR(1), VARCHAR2(1) columns are typecasted to booleans then you can add the following line to your initializer file:

ActiveRecord::ConnectionAdapters::OracleEnhancedAdapter.emulate_booleans_from_strings = true



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 186

cattr_accessor :emulate_booleans_from_strings

#get_database_version ⇒ Object 



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 680

def get_database_version
  @connection.database_version
end

#has_primary_key?(table_name, owner = nil, desc_table_name = nil) ⇒ Boolean

:nodoc:

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 631

def has_primary_key?(table_name, owner = nil, desc_table_name = nil) #:nodoc:
  !pk_and_sequence_for(table_name, owner, desc_table_name).nil?
end

#max_identifier_length ⇒ Object Also known as: table_alias_length, index_name_length 



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 674

def max_identifier_length
  supports_longer_identifier? ? 128 : 30
end

#native_database_types ⇒ Object

:startdoc:



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 413

def native_database_types #:nodoc:
  emulate_booleans_from_strings ? NATIVE_DATABASE_TYPES_BOOLEAN_STRINGS : NATIVE_DATABASE_TYPES
end

#next_sequence_value(sequence_name) ⇒ Object

Returns the next sequence value from a sequence generator. Not generally called directly; used by ActiveRecord to get the next primary key value when inserting a new database record (see #prefetch_primary_key?).



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 477

def next_sequence_value(sequence_name)
  # if sequence_name is set to :autogenerated then it means that primary key will be populated by trigger
  raise ArgumentError.new "Trigger based primary key is not supported" if sequence_name == AUTOGENERATED_SEQUENCE_NAME
  # call directly connection method to avoid prepared statement which causes fetching of next sequence value twice
  select_value(<<~SQL.squish, "SCHEMA")
    SELECT #{quote_table_name(sequence_name)}.NEXTVAL FROM dual
  SQL
end

#permissions ⇒ Object

:singleton-method: By default, OracleEnhanced adapter will grant unlimited tablespace, create session, create table, create view, and create sequence when running the rake task db:create.

If you wish to change these permissions you can add the following line to your initializer file:

ActiveRecord::ConnectionAdapters::OracleEnhancedAdapter.permissions =
["create session", "create table", "create view", "create sequence", "create trigger", "ctxapp"]



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 228

cattr_accessor :permissions

#pk_and_sequence_for(table_name, owner = nil, desc_table_name = nil) ⇒ Object

Find a table's primary key and sequence. Note: Only primary key is implemented - sequence will be nil.



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 593

def pk_and_sequence_for(table_name, owner = nil, desc_table_name = nil) #:nodoc:
  (owner, desc_table_name) = @connection.describe(table_name)

  seqs = select_values(<<~SQL.squish, "SCHEMA")
    select /*+ OPTIMIZER_FEATURES_ENABLE('11.2.0.2') */ us.sequence_name
    from all_sequences us
    where us.sequence_owner = '#{owner}'
    and us.sequence_name = upper(#{quote(default_sequence_name(desc_table_name))})
  SQL

  # changed back from user_constraints to all_constraints for consistency
  pks = select_values(<<~SQL.squish, "SCHEMA")
    SELECT /*+ OPTIMIZER_FEATURES_ENABLE('11.2.0.2') */ cc.column_name
      FROM all_constraints c, all_cons_columns cc
     WHERE c.owner = '#{owner}'
       AND c.table_name = #{quote(desc_table_name)}
       AND c.constraint_type = 'P'
       AND cc.owner = c.owner
       AND cc.constraint_name = c.constraint_name
  SQL

  warn <<~WARNING if pks.count > 1
    WARNING: Active Record does not support composite primary key.

    #{table_name} has composite primary key. Composite primary key is ignored.
  WARNING

  # only support single column keys
  pks.size == 1 ? [oracle_downcase(pks.first),
                   oracle_downcase(seqs.first)] : nil
end

#prefetch_primary_key?(table_name = nil) ⇒ Boolean

Returns true for Oracle adapter (since Oracle requires primary key values to be pre-fetched before insert). See also #next_sequence_value.

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 488

def prefetch_primary_key?(table_name = nil)
  return true if table_name.nil?
  table_name = table_name.to_s
  do_not_prefetch = @do_not_prefetch_primary_key[table_name]
  if do_not_prefetch.nil?
    owner, desc_table_name = @connection.describe(table_name)
    @do_not_prefetch_primary_key [table_name] = do_not_prefetch = !has_primary_key?(table_name, owner, desc_table_name)
  end
  !do_not_prefetch
end

#primary_key(table_name) ⇒ Object

Returns just a table's primary key



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 626

def primary_key(table_name)
  pk_and_sequence = pk_and_sequence_for(table_name)
  pk_and_sequence && pk_and_sequence.first
end

#primary_keys(table_name) ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 635

def primary_keys(table_name) # :nodoc:
  (_owner, desc_table_name) = @connection.describe(table_name)

  pks = select_values(<<~SQL.squish, "SCHEMA", [bind_string("table_name", desc_table_name)])
    SELECT /*+ OPTIMIZER_FEATURES_ENABLE('11.2.0.2') */ cc.column_name
      FROM all_constraints c, all_cons_columns cc
     WHERE c.owner = SYS_CONTEXT('userenv', 'current_schema')
       AND c.table_name = :table_name
       AND c.constraint_type = 'P'
       AND cc.owner = c.owner
       AND cc.constraint_name = c.constraint_name
       order by cc.position
  SQL
  pks.map { |pk| oracle_downcase(pk) }
end

#raw_connection ⇒ Object

return raw OCI8 or JDBC connection



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 432

def raw_connection
  @connection.raw_connection
end

#reconnect! ⇒ Object

Reconnects to the database.



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 448

def reconnect! #:nodoc:
  super
  @connection.reset!
rescue OracleEnhanced::ConnectionException => e
  @logger.warn "#{adapter_name} automatic reconnection failed: #{e.message}" if @logger
end

#reset! ⇒ Object 



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 455

def reset!
  clear_cache!
  super
end

#reset_pk_sequence!(table_name, primary_key = nil, sequence_name = nil) ⇒ Object

:nodoc:



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 499

def reset_pk_sequence!(table_name, primary_key = nil, sequence_name = nil) #:nodoc:
  return nil unless data_source_exists?(table_name)
  unless primary_key && sequence_name
    # *Note*: Only primary key is implemented - sequence will be nil.
    primary_key, sequence_name = pk_and_sequence_for(table_name)
    # TODO This sequence_name implemantation is just enough
    # to satisty fixures. To get correct sequence_name always
    # pk_and_sequence_for method needs some work.
    begin
      sequence_name = table_name.classify.constantize.sequence_name
    rescue
      sequence_name = default_sequence_name(table_name)
    end
  end

  if @logger && primary_key && !sequence_name
    @logger.warn "#{table_name} has primary key #{primary_key} with no default sequence"
  end

  if primary_key && sequence_name
    new_start_value = select_value(<<~SQL.squish, "SCHEMA")
      select NVL(max(#{quote_column_name(primary_key)}),0) + 1 from #{quote_table_name(table_name)}
    SQL

    execute "DROP SEQUENCE #{quote_table_name(sequence_name)}"
    execute "CREATE SEQUENCE #{quote_table_name(sequence_name)} START WITH #{new_start_value}"
  end
end

#supports_comments? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 311

def supports_comments?
  true
end

#supports_common_table_expressions? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 291

def supports_common_table_expressions?
  true
end

#supports_datetime_with_precision? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 307

def supports_datetime_with_precision?
  true
end

#supports_fetch_first_n_rows_and_offset? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 299

def supports_fetch_first_n_rows_and_offset?
  if !use_old_oracle_visitor && database_version.first >= 12
    true
  else
    false
  end
end

#supports_foreign_keys? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 283

def supports_foreign_keys?
  true
end

#supports_json? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 323

def supports_json?
  # Oracle Database 12.1 or higher version supports JSON.
  # However, Oracle enhanced adapter has limited support for JSON data type.
  # which does not pass many of ActiveRecord JSON tests.
  #
  # No migration supported for :json type due to there is no `JSON` data type
  # in Oracle Database itself.
  #
  # If you want to use JSON data type, here are steps
  # 1.Define :string or :text in migration
  #
  # create_table :test_posts, force: true do |t|
  #   t.string  :title
  #   t.text    :article
  # end
  #
  # 2. Set :json attributes
  #
  # class TestPost < ActiveRecord::Base
  #  attribute :title, :json
  #  attribute :article, :json
  # end
  #
  # 3. Add `is json` database constraints by running sql statements
  #
  # alter table test_posts add constraint test_posts_title_is_json check (title is json)
  # alter table test_posts add constraint test_posts_article_is_json check (article is json)
  #
  false
end

#supports_longer_identifier? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 354

def supports_longer_identifier?
  if !use_shorter_identifier && database_version.to_s >= [12, 2].to_s
    true
  else
    false
  end
end

#supports_multi_insert? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 315

def supports_multi_insert?
  database_version.to_s >= [11, 2].to_s
end

#supports_optimizer_hints? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 287

def supports_optimizer_hints?
  true
end

#supports_savepoints? ⇒ Boolean

:nodoc:

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 275

def supports_savepoints? #:nodoc:
  true
end

#supports_transaction_isolation? ⇒ Boolean

:nodoc:

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 279

def supports_transaction_isolation? #:nodoc:
  true
end

#supports_views? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 295

def supports_views?
  true
end

#supports_virtual_columns? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 319

def supports_virtual_columns?
  database_version.first >= 11
end

#temporary_table?(table_name) ⇒ Boolean

:nodoc:

Returns:

  • (Boolean) 


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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 667

def temporary_table?(table_name) #:nodoc:
  select_value(<<~SQL.squish, "SCHEMA", [bind_string("table_name", table_name.upcase)]) == "Y"
    SELECT /*+ OPTIMIZER_FEATURES_ENABLE('11.2.0.2') */
    temporary FROM all_tables WHERE table_name = :table_name and owner = SYS_CONTEXT('userenv', 'current_schema')
  SQL
end

#use_old_oracle_visitor ⇒ Object

:singleton-method: By default, OracleEnhanced adapter will use Oracle12 visitor if database version is Oracle 12.1. If you wish to use Oracle visitor which is intended to work with Oracle 11.2 or lower for Oracle 12.1 database you can add the following line to your initializer file:

ActiveRecord::ConnectionAdapters::OracleEnhancedAdapter.use_old_oracle_visitor = true



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 197

cattr_accessor :use_old_oracle_visitor

#use_shorter_identifier ⇒ Object

:singleton-method: By default, OracleEnhanced adapter will use longer 128 bytes identifier if database version is Oracle 12.2 or higher. If you wish to use shorter 30 byte identifier with Oracle Database supporting longer identifier you can add the following line to your initializer file:

ActiveRecord::ConnectionAdapters::OracleEnhancedAdapter.use_shorter_identifier = true



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# File 'lib/active_record/connection_adapters/oracle_enhanced_adapter.rb', line 216

cattr_accessor :use_shorter_identifier