# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 627 def primary_key(table_name) pk_and_sequence = pk_and_sequence_for(table_name) pk_and_sequence && pk_and_sequence.first end
class ActiveRecord::ConnectionAdapters::OracleEnhancedAdapter
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 -
:jdbc_statement_cache_size
- number of cached SQL cursors to keep open, disabled per default (for unpooled JDBC only)
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 toCHAR
(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 isYYYY-MM-DD HH24:MI:SS
-
:nls_timestamp_format
- format for :timestamp columns isYYYY-MM-DD HH24:MI:SS:FF6
Constants
- ADAPTER_NAME
- AUTOGENERATED_SEQUENCE_NAME
use in set_sequence_name to avoid fetching primary key value from sequence
- TYPE_MAP
- VERSION
Public Class Methods
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
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 260 def self.database_exists?(config) raise NotImplementedError end
Specify default sequence start with value (by default 1 if not explicitly set), e.g.:
ActiveRecord::ConnectionAdapters::OracleEnhancedAdapter.default_sequence_start_value = 10000
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 206 cattr_accessor :default_sequence_start_value
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.
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 178 cattr_accessor :default_tablespaces
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
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 165 cattr_accessor :emulate_booleans
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
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 187 cattr_accessor :emulate_booleans_from_strings
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"]
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 229 cattr_accessor :permissions
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
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 198 cattr_accessor :use_old_oracle_visitor
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
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 217 cattr_accessor :use_shorter_identifier
Private Class Methods
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 695 def initialize_type_map(m) super # oracle register_class_with_precision m, %r(WITH TIME ZONE)i, Type::OracleEnhanced::TimestampTz register_class_with_precision m, %r(WITH LOCAL TIME ZONE)i, Type::OracleEnhanced::TimestampLtz register_class_with_limit m, %r(raw)i, Type::OracleEnhanced::Raw register_class_with_limit m, %r{^(char)}i, Type::OracleEnhanced::CharacterString register_class_with_limit m, %r{^(nchar)}i, Type::OracleEnhanced::String register_class_with_limit m, %r(varchar)i, Type::OracleEnhanced::String register_class_with_limit m, %r(clob)i, Type::OracleEnhanced::Text register_class_with_limit m, %r(nclob)i, Type::OracleEnhanced::NationalCharacterText m.register_type "NCHAR", Type::OracleEnhanced::NationalCharacterString.new m.alias_type %r(NVARCHAR2)i, "NCHAR" m.register_type(%r(NUMBER)i) do |sql_type| scale = extract_scale(sql_type) precision = extract_precision(sql_type) limit = extract_limit(sql_type) if scale == 0 Type::OracleEnhanced::Integer.new(precision: precision, limit: limit) else Type::Decimal.new(precision: precision, scale: scale) end end if OracleEnhancedAdapter.emulate_booleans m.register_type %r(^NUMBER\(1\))i, Type::Boolean.new end end
Public Instance Methods
create bind object for type String
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 771 def bind_string(name, value) ActiveRecord::Relation::QueryAttribute.new(name, value, Type::OracleEnhanced::String.new) end
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 272 def build_statement_pool StatementPool.new(self.class.type_cast_config_to_integer(@config[:statement_limit])) end
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 685 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
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 588 def clear_table_columns_cache(table_name) @columns_cache[table_name.to_s] = nil end
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 562 def column_definitions(table_name) (owner, desc_table_name) = @connection.describe(table_name) select_all(<<~SQL.squish, "SCHEMA", [bind_string("owner", owner), bind_string("table_name", desc_table_name)]) 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 = :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
Current database name
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 530 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 database session schema
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 548 def current_schema select_value(<<~SQL.squish, "SCHEMA") SELECT SYS_CONTEXT('userenv', 'current_schema') FROM dual SQL end
Current database session user
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 541 def current_user select_value(<<~SQL.squish, "SCHEMA") SELECT SYS_CONTEXT('userenv', 'session_user') FROM dual SQL end
Default tablespace name of current user
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 555 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
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 467 def discard! super @connection = nil end
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 733 def extract_value_from_default(default) case default when String default.gsub("''", "'") else default end end
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 681 def get_database_version @connection.database_version end
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 675 def max_identifier_length supports_longer_identifier? ? 128 : 30 end
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?
).
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 478 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
Returns true for Oracle adapter (since Oracle requires primary key values to be pre-fetched before insert). See also next_sequence_value
.
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 489 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
Returns just a table’s primary key
return raw OCI8 or JDBC connection
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 433 def raw_connection @connection.raw_connection end
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 456 def reset! clear_cache! super end
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 787 def select_value_forcing_binds(arel, name, binds) single_value_from_rows(select_values_forcing_binds(arel, name, binds)) end
call select_values using binds even if surrounding SQL preparation/execution is done + # with conn.unprepared_statement (like AR.to_sql)
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 776 def select_values_forcing_binds(arel, name, binds) # remove possible force of unprepared SQL during dictionary access unprepared_statement_forced = prepared_statements_disabled_cache.include?(object_id) prepared_statements_disabled_cache.delete(object_id) if unprepared_statement_forced select_values(arel, name, binds) ensure # Restore unprepared_statement setting for surrounding SQL prepared_statements_disabled_cache.add(object_id) if unprepared_statement_forced end
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 312 def supports_comments? true end
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 292 def supports_common_table_expressions? true end
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 308 def supports_datetime_with_precision? true end
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 300 def supports_fetch_first_n_rows_and_offset? if !use_old_oracle_visitor && database_version.first >= 12 true else false end end
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 284 def supports_foreign_keys? true end
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 324 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
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 355 def supports_longer_identifier? if !use_shorter_identifier && database_version.to_s >= [12, 2].to_s true else false end end
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 316 def supports_multi_insert? database_version.to_s >= [11, 2].to_s end
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 288 def supports_optimizer_hints? true end
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 296 def supports_views? true end
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 320 def supports_virtual_columns? database_version.first >= 11 end
# File lib/active_record/connection_adapters/oracle_enhanced_adapter.rb, line 729 def type_map TYPE_MAP end