Active Record Abstract Adapter

Active Record supports multiple database systems. AbstractAdapter and related classes form the abstraction layer which makes this possible. An AbstractAdapter represents a connection to a database, and provides an abstract interface for database-specific functionality such as establishing a connection, escaping values, building the right SQL fragments for :offset and :limit options, etc.

All the concrete database adapters follow the interface laid down in this class. ActiveRecord::Base.lease_connection returns an AbstractAdapter object, which you can use.

Most of the methods in the adapter are useful during migrations. Most notably, the instance methods provided by SchemaStatements are very useful.

Namespace

Class

ActiveRecord::ConnectionAdapters::AbstractAdapter::Version

Methods

active?
adapter_name
check_all_foreign_keys_valid!
clear_cache!
close
connect!
connected?
connection_retries
database_exists?
database_exists?
dbconsole
default_timezone
disable_extension
disable_referential_integrity
discard!
disconnect!
enable_extension
expire
extensions
find_cmd_and_exec
index_algorithms
lease
log
pool=
prefetch_primary_key?
prepared_statements
prepared_statements?
preventing_writes?
raw_connection
reconnect!
replica?
requires_reloading?
reset!
retry_deadline
role
savepoint_errors_invalidate_transactions?
schema_cache
schema_version
shard
supports_advisory_locks?
supports_bulk_alter?
supports_check_constraints?
supports_comments?
supports_comments_in_create?
supports_common_table_expressions?
supports_concurrent_connections?
supports_datetime_with_precision?
supports_ddl_transactions?
supports_deferrable_constraints?
supports_exclusion_constraints?
supports_explain?
supports_expression_index?
supports_extensions?
supports_foreign_keys?
supports_foreign_tables?
supports_index_include?
supports_index_sort_order?
supports_indexes_in_create?
supports_insert_conflict_target?
supports_insert_on_duplicate_skip?
supports_insert_on_duplicate_update?
supports_insert_returning?
supports_json?
supports_lazy_transactions?
supports_materialized_views?
supports_nulls_not_distinct?
supports_optimizer_hints?
supports_partial_index?
supports_partitioned_indexes?
supports_restart_db_transaction?
supports_savepoints?
supports_transaction_isolation?
supports_unique_constraints?
supports_validate_constraints?
supports_views?
supports_virtual_columns?
throw_away!
type_cast_config_to_boolean
type_cast_config_to_integer
unprepared_statement
validate_default_timezone
verify!

Included Modules

Constants

ADAPTER_NAME	=	"Abstract"
COMMENT_REGEX	=	%r{(?:--.\n)\|/\(?:[^]\|\[^/])\/}
EXTENDED_TYPE_MAPS	=	Concurrent::Map.new
SIMPLE_INT	=	/\A\d+\z/
TYPE_MAP	=	Type::TypeMap.new.tap { \|m\| initialize_type_map(m) }

Attributes

[R]	in_use?
[R]	lock
[R]	logger
[R]	owner
[R]	pool
[R]	visitor

Class Public methods

database_exists?(config)

Does the database for this adapter exist?

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 354
      def self.database_exists?(config)
        new(config).database_exists?
      end

🔎 See on GitHub

dbconsole(config, options = {})

Opens a database console session.

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 122
      def self.dbconsole(config, options = {})
        raise NotImplementedError
      end

🔎 See on GitHub

find_cmd_and_exec(commands, *args)

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 93
      def self.find_cmd_and_exec(commands, *args) # :doc:
        commands = Array(commands)

        dirs_on_path = ENV["PATH"].to_s.split(File::PATH_SEPARATOR)
        unless (ext = RbConfig::CONFIG["EXEEXT"]).empty?
          commands = commands.map { |cmd| "#{cmd}#{ext}" }
        end

        full_path_command = nil
        found = commands.detect do |cmd|
          dirs_on_path.detect do |path|
            full_path_command = File.join(path, cmd)
            begin
              stat = File.stat(full_path_command)
            rescue SystemCallError
            else
              stat.file? && stat.executable?
            end
          end
        end

        if found
          exec full_path_command, *args
        else
          abort("Couldn't find database client: #{commands.join(', ')}. Check your $PATH and try again.")
        end
      end

🔎 See on GitHub

type_cast_config_to_boolean(config)

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 66
      def self.type_cast_config_to_boolean(config)
        if config == "false"
          false
        else
          config
        end
      end

🔎 See on GitHub

type_cast_config_to_integer(config)

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 56
      def self.type_cast_config_to_integer(config)
        if config.is_a?(Integer)
          config
        elsif SIMPLE_INT.match?(config)
          config.to_i
        else
          config
        end
      end

🔎 See on GitHub

validate_default_timezone(config)

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 74
      def self.validate_default_timezone(config)
        case config
        when nil
        when "utc", "local"
          config.to_sym
        else
          raise ArgumentError, "default_timezone must be either 'utc' or 'local'"
        end
      end

🔎 See on GitHub

Instance Public methods

active?()

Checks whether the connection to the database is still active. This includes checking whether the database is actually capable of responding, i.e. whether the connection isn’t stale.

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 644
      def active?
      end

🔎 See on GitHub

adapter_name()

Returns the human-readable name of the adapter. Use mixed case - one can always use downcase if needed.

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 349
      def adapter_name
        self.class::ADAPTER_NAME
      end

🔎 See on GitHub

check_all_foreign_keys_valid!()

Override to check all foreign key constraints in a database. The adapter should raise a ActiveRecord::StatementInvalid if foreign key constraints are not met.

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 629
      def check_all_foreign_keys_valid!
      end

🔎 See on GitHub

clear_cache!(new_connection: false)

Clear any caching the database adapter may be doing.

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 725
      def clear_cache!(new_connection: false)
        if @statements
          @lock.synchronize do
            if new_connection
              @statements.reset
            else
              @statements.clear
            end
          end
        end
      end

🔎 See on GitHub

close()

Check the connection back in to the connection pool

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 815
      def close
        pool.checkin self
      end

🔎 See on GitHub

connect!()

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 763
      def connect!
        verify!
        self
      end

🔎 See on GitHub

connected?()

Checks whether the connection to the database was established. This doesn’t include checking whether the database is actually capable of responding, i.e. whether the connection is stale.

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 637
      def connected?
        !@raw_connection.nil?
      end

🔎 See on GitHub

connection_retries()

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 210
      def connection_retries
        (@config[:connection_retries] || 1).to_i
      end

🔎 See on GitHub

database_exists?()

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 358
      def database_exists?
        connect!
        true
      rescue ActiveRecord::NoDatabaseError
        false
      end

🔎 See on GitHub

default_timezone()

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 222
      def default_timezone
        @default_timezone || ActiveRecord.default_timezone
      end

🔎 See on GitHub

disable_extension(name, **)

This is meant to be implemented by the adapters that support extensions

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 564
      def disable_extension(name, **)
      end

🔎 See on GitHub

disable_referential_integrity()

Override to turn off referential integrity while executing &block.

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 622
      def disable_referential_integrity
        yield
      end

🔎 See on GitHub

discard!()

Immediately forget this connection ever existed. Unlike disconnect!, this will not communicate with the server.

After calling this method, the behavior of all other methods becomes undefined. This is called internally just before a forked process gets rid of a connection that belonged to its parent.

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 700
      def discard!
        # This should be overridden by concrete adapters.
      end

🔎 See on GitHub

disconnect!()

Disconnects from the database if already connected. Otherwise, this method does nothing.

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 686
      def disconnect!
        @lock.synchronize do
          clear_cache!(new_connection: true)
          reset_transaction
          @raw_connection_dirty = false
        end
      end

🔎 See on GitHub

enable_extension(name, **)

This is meant to be implemented by the adapters that support extensions

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 568
      def enable_extension(name, **)
      end

🔎 See on GitHub

expire()

this method must only be called while holding connection pool’s mutex

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 306
      def expire
        if in_use?
          if @owner != ActiveSupport::IsolatedExecutionState.context
            raise ActiveRecordError, "Cannot expire connection, " \
              "it is owned by a different thread: #{@owner}. " \
              "Current thread: #{ActiveSupport::IsolatedExecutionState.context}."
          end

          @idle_since = Process.clock_gettime(Process::CLOCK_MONOTONIC)
          @owner = nil
        else
          raise ActiveRecordError, "Cannot expire connection, it is not currently leased."
        end
      end

🔎 See on GitHub

extensions()

A list of extensions, to be filled in by adapters that support them.

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 610
      def extensions
        []
      end

🔎 See on GitHub

index_algorithms()

A list of index algorithms, to be filled by adapters that support them.

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 615
      def index_algorithms
        {}
      end

🔎 See on GitHub

lease()

this method must only be called while holding connection pool’s mutex

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 270
      def lease
        if in_use?
          msg = +"Cannot lease connection, "
          if @owner == ActiveSupport::IsolatedExecutionState.context
            msg << "it is already leased by the current thread."
          else
            msg << "it is already in use by a different thread: #{@owner}. " \
                   "Current thread: #{ActiveSupport::IsolatedExecutionState.context}."
          end
          raise ActiveRecordError, msg
        end

        @owner = ActiveSupport::IsolatedExecutionState.context
      end

🔎 See on GitHub

pool=(value)

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 48
      def pool=(value)
        return if value.eql?(@pool)
        @schema_cache = nil
        @pool = value
      end

🔎 See on GitHub

prefetch_primary_key?(table_name = nil)

Should primary key values be selected from their corresponding sequence before the insert statement? If true, next_sequence_value is called before each insert to set the record’s primary key.

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 398
      def prefetch_primary_key?(table_name = nil)
        false
      end

🔎 See on GitHub

prepared_statements()

Alias for: prepared_statements?

prepared_statements?()

Also aliased as: prepared_statements

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 237
      def prepared_statements?
        @prepared_statements && !prepared_statements_disabled_cache.include?(object_id)
      end

🔎 See on GitHub

preventing_writes?()

Determines whether writes are currently being prevented.

Returns true if the connection is a replica or returns the value of current_preventing_writes.

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 230
      def preventing_writes?
        return true if replica?
        return false if connection_class.nil?

        connection_class.current_preventing_writes
      end

🔎 See on GitHub

raw_connection()

Provides access to the underlying database driver for this adapter. For example, this method returns a Mysql2::Client object in case of Mysql2Adapter, and a PG::Connection object in case of PostgreSQLAdapter.

This is useful for when you need to call a proprietary method such as PostgreSQL’s lo_* methods.

Active Record cannot track if the database is getting modified using this client. If that is the case, generally you’ll want to invalidate the query cache using ActiveRecord::Base.clear_query_cache.

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 783
      def raw_connection
        with_raw_connection do |conn|
          disable_lazy_transactions!
          @raw_connection_dirty = true
          conn
        end
      end

🔎 See on GitHub

reconnect!(restore_transactions: false)

Disconnects from the database if already connected, and establishes a new connection with the database. Implementors should define private reconnect instead.

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 650
      def reconnect!(restore_transactions: false)
        retries_available = connection_retries
        deadline = retry_deadline && Process.clock_gettime(Process::CLOCK_MONOTONIC) + retry_deadline

        @lock.synchronize do
          reconnect

          enable_lazy_transactions!
          @raw_connection_dirty = false
          @verified = true

          reset_transaction(restore: restore_transactions) do
            clear_cache!(new_connection: true)
            configure_connection
          end
        rescue => original_exception
          translated_exception = translate_exception_class(original_exception, nil, nil)
          retry_deadline_exceeded = deadline && deadline < Process.clock_gettime(Process::CLOCK_MONOTONIC)

          if !retry_deadline_exceeded && retries_available > 0
            retries_available -= 1

            if retryable_connection_error?(translated_exception)
              backoff(connection_retries - retries_available)
              retry
            end
          end

          @verified = false

          raise translated_exception
        end
      end

🔎 See on GitHub

replica?()

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 206
      def replica?
        @config[:replica] || false
      end

🔎 See on GitHub

requires_reloading?()

Returns true if its required to reload the connection between requests for development mode.

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 738
      def requires_reloading?
        false
      end

🔎 See on GitHub

reset!()

Reset the state of this connection, directing the DBMS to clear transactions and other connection-related server-side state. Usually a database-dependent operation.

If a database driver or protocol does not support such a feature, implementors may alias this to reconnect!. Otherwise, implementors should call super immediately after resetting the connection (and while still holding @lock).

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 712
      def reset!
        clear_cache!(new_connection: true)
        reset_transaction
        configure_connection
      end

🔎 See on GitHub

retry_deadline()

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 214
      def retry_deadline
        if @config[:retry_deadline]
          @config[:retry_deadline].to_f
        else
          nil
        end
      end

🔎 See on GitHub

role()

The role (e.g. :writing) for the current connection. In a non-multi role application, :writing is returned.

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 291
      def role
        @pool.role
      end

🔎 See on GitHub

savepoint_errors_invalidate_transactions?()

Do TransactionRollbackErrors on savepoints affect the parent transaction?

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 382
      def savepoint_errors_invalidate_transactions?
        false
      end

🔎 See on GitHub

schema_cache()

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 301
      def schema_cache
        @pool.schema_cache || (@schema_cache ||= BoundSchemaReflection.for_lone_connection(@pool.schema_reflection, self))
      end

🔎 See on GitHub

schema_version()

Returns the version identifier of the schema currently available in the database. This is generally equal to the number of the highest- numbered migration that has been executed, or 0 if no schema information is present / the database is empty.

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 850
      def schema_version
        pool.migration_context.current_version
      end

🔎 See on GitHub

shard()

The shard (e.g. :default) for the current connection. In a non-sharded application, :default is returned.

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 297
      def shard
        @pool.shard
      end

🔎 See on GitHub

supports_advisory_locks?()

Does this adapter support application-enforced advisory locking?

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 391
      def supports_advisory_locks?
        false
      end

🔎 See on GitHub

supports_bulk_alter?()

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 371
      def supports_bulk_alter?
        false
      end

🔎 See on GitHub

supports_check_constraints?()

Does this adapter support creating check constraints?

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 463
      def supports_check_constraints?
        false
      end

🔎 See on GitHub

supports_comments?()

Does this adapter support metadata comments on database objects (tables, columns, indexes)?

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 498
      def supports_comments?
        false
      end

🔎 See on GitHub

supports_comments_in_create?()

Can comments for tables, columns, and indexes be specified in create/alter table statements?

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 503
      def supports_comments_in_create?
        false
      end

🔎 See on GitHub

supports_common_table_expressions?()

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 522
      def supports_common_table_expressions?
        false
      end

🔎 See on GitHub

supports_concurrent_connections?()

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 546
      def supports_concurrent_connections?
        true
      end

🔎 See on GitHub

supports_datetime_with_precision?()

Does this adapter support datetime with precision?

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 488
      def supports_datetime_with_precision?
        false
      end

🔎 See on GitHub

supports_ddl_transactions?()

Does this adapter support DDL rollbacks in transactions? That is, would CREATE TABLE or ALTER TABLE get rolled back by a transaction?

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 367
      def supports_ddl_transactions?
        false
      end

🔎 See on GitHub

supports_deferrable_constraints?()

Does this adapter support creating deferrable constraints?

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 458
      def supports_deferrable_constraints?
        false
      end

🔎 See on GitHub

supports_exclusion_constraints?()

Does this adapter support creating exclusion constraints?

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 468
      def supports_exclusion_constraints?
        false
      end

🔎 See on GitHub

supports_explain?()

Does this adapter support explain?

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 427
      def supports_explain?
        false
      end

🔎 See on GitHub

supports_expression_index?()

Does this adapter support expression indices?

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 422
      def supports_expression_index?
        false
      end

🔎 See on GitHub

supports_extensions?()

Does this adapter support database extensions?

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 437
      def supports_extensions?
        false
      end

🔎 See on GitHub

supports_foreign_keys?()

Does this adapter support creating foreign key constraints?

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 448
      def supports_foreign_keys?
        false
      end

🔎 See on GitHub

supports_foreign_tables?()

Does this adapter support foreign/external tables?

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 513
      def supports_foreign_tables?
        false
      end

🔎 See on GitHub

supports_index_include?()

Does this adapter support including non-key columns?

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 417
      def supports_index_include?
        false
      end

🔎 See on GitHub

supports_index_sort_order?()

Does this adapter support index sort order?

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 407
      def supports_index_sort_order?
        false
      end

🔎 See on GitHub

supports_indexes_in_create?()

Does this adapter support creating indexes in the same statement as creating the table?

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 443
      def supports_indexes_in_create?
        false
      end

🔎 See on GitHub

supports_insert_conflict_target?()

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 542
      def supports_insert_conflict_target?
        false
      end

🔎 See on GitHub

supports_insert_on_duplicate_skip?()

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 534
      def supports_insert_on_duplicate_skip?
        false
      end

🔎 See on GitHub

supports_insert_on_duplicate_update?()

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 538
      def supports_insert_on_duplicate_update?
        false
      end

🔎 See on GitHub

supports_insert_returning?()

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 530
      def supports_insert_returning?
        false
      end

🔎 See on GitHub

supports_json?()

Does this adapter support JSON data type?

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 493
      def supports_json?
        false
      end

🔎 See on GitHub

supports_lazy_transactions?()

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 526
      def supports_lazy_transactions?
        false
      end

🔎 See on GitHub

supports_materialized_views?()

Does this adapter support materialized views?

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 483
      def supports_materialized_views?
        false
      end

🔎 See on GitHub

supports_nulls_not_distinct?()

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 550
      def supports_nulls_not_distinct?
        false
      end

🔎 See on GitHub

supports_optimizer_hints?()

Does this adapter support optimizer hints?

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 518
      def supports_optimizer_hints?
        false
      end

🔎 See on GitHub

supports_partial_index?()

Does this adapter support partial indices?

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 412
      def supports_partial_index?
        false
      end

🔎 See on GitHub

supports_partitioned_indexes?()

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 402
      def supports_partitioned_indexes?
        false
      end

🔎 See on GitHub

supports_restart_db_transaction?()

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 386
      def supports_restart_db_transaction?
        false
      end

🔎 See on GitHub

supports_savepoints?()

Does this adapter support savepoints?

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 376
      def supports_savepoints?
        false
      end

🔎 See on GitHub

supports_transaction_isolation?()

Does this adapter support setting the isolation level for a transaction?

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 432
      def supports_transaction_isolation?
        false
      end

🔎 See on GitHub

supports_unique_constraints?()

Does this adapter support creating unique constraints?

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 473
      def supports_unique_constraints?
        false
      end

🔎 See on GitHub

supports_validate_constraints?()

Does this adapter support creating invalid constraints?

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 453
      def supports_validate_constraints?
        false
      end

🔎 See on GitHub

supports_views?()

Does this adapter support views?

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 478
      def supports_views?
        false
      end

🔎 See on GitHub

supports_virtual_columns?()

Does this adapter support virtual columns?

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 508
      def supports_virtual_columns?
        false
      end

🔎 See on GitHub

throw_away!()

Removes the connection from the pool and disconnect it.

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 719
      def throw_away!
        pool.remove self
        disconnect!
      end

🔎 See on GitHub

unprepared_statement()

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 340
      def unprepared_statement
        cache = prepared_statements_disabled_cache.add?(object_id) if @prepared_statements
        yield
      ensure
        cache&.delete(object_id)
      end

🔎 See on GitHub

verify!()

Checks whether the connection to the database is still active (i.e. not stale). This is done under the hood by calling active?. If the connection is no longer active, then this method will reconnect to the database.

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 745
      def verify!
        unless active?
          @lock.synchronize do
            if @unconfigured_connection
              @raw_connection = @unconfigured_connection
              @unconfigured_connection = nil
              configure_connection
              @verified = true
              return
            end

            reconnect!(restore_transactions: true)
          end
        end

        @verified = true
      end

🔎 See on GitHub

Instance Private methods

log(sql, name = "SQL", binds = [], type_casted_binds = [], statement_name = nil, async: false, &block)

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 1111
        def log(sql, name = "SQL", binds = [], type_casted_binds = [], statement_name = nil, async: false, &block) # :doc:
          @instrumenter.instrument(
            "sql.active_record",
            sql:               sql,
            name:              name,
            binds:             binds,
            type_casted_binds: type_casted_binds,
            statement_name:    statement_name,
            async:             async,
            connection:        self,
            transaction:       current_transaction.presence,
            row_count:         0,
            &block
          )
        rescue ActiveRecord::StatementInvalid => ex
          raise ex.set_query(sql, binds)
        end

🔎 See on GitHub

ActiveRecord::ConnectionAdapters::AbstractAdapter < Object

Active Record Abstract Adapter

Namespace

Class

Methods

Included Modules

Constants

Attributes

Class Public methods

database_exists?(config)

dbconsole(config, options = {})

find_cmd_and_exec(commands, *args)

type_cast_config_to_boolean(config)

type_cast_config_to_integer(config)

validate_default_timezone(config)

Instance Public methods

active?()

adapter_name()

check_all_foreign_keys_valid!()

clear_cache!(new_connection: false)

close()

connect!()

connected?()

connection_retries()

database_exists?()

default_timezone()

disable_extension(name, **)

disable_referential_integrity()

discard!()

disconnect!()

enable_extension(name, **)

expire()

extensions()

index_algorithms()

lease()

pool=(value)

prefetch_primary_key?(table_name = nil)

prepared_statements()

prepared_statements?()

preventing_writes?()

raw_connection()

reconnect!(restore_transactions: false)

replica?()

requires_reloading?()

reset!()

retry_deadline()

role()

savepoint_errors_invalidate_transactions?()

schema_cache()

schema_version()

shard()

supports_advisory_locks?()

supports_bulk_alter?()

supports_check_constraints?()

supports_comments?()

supports_comments_in_create?()

supports_common_table_expressions?()

supports_concurrent_connections?()

supports_datetime_with_precision?()

supports_ddl_transactions?()

supports_deferrable_constraints?()

supports_exclusion_constraints?()

supports_explain?()

supports_expression_index?()

supports_extensions?()

supports_foreign_keys?()

supports_foreign_tables?()

supports_index_include?()

supports_index_sort_order?()

supports_indexes_in_create?()

supports_insert_conflict_target?()

supports_insert_on_duplicate_skip?()

supports_insert_on_duplicate_update?()

supports_insert_returning?()

supports_json?()

supports_lazy_transactions?()

supports_materialized_views?()

supports_nulls_not_distinct?()

supports_optimizer_hints?()

supports_partial_index?()