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
extensions
find_cmd_and_exec
index_algorithms
lease
log
max_jitter
pool=
pool_jitter
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_disabling_indexes?
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!
verify_timeout

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 403
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 128
def self.dbconsole(config, options = {})
  raise NotImplementedError.new("#{self.class} should define `dbconsole` that accepts a db config and options to implement connecting to the db console")
end

🔎 See on GitHub

`find_cmd_and_exec(commands, *args)`

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 99
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 72
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 62
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 80
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 705
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 398
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 690
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 792
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 892
def close
  pool.checkin self
end

🔎 See on GitHub

`connect!()`

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 833
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 698
def connected?
  !@raw_connection.nil?
end

🔎 See on GitHub

`connection_retries()`

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 221
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 407
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 237
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 617
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 683
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 767
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 752
def disconnect!
  @lock.synchronize do
    clear_cache!(new_connection: true)
    reset_transaction
    @raw_connection_dirty = false
    @connected_since = nil
  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 621
def enable_extension(name, **)
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 671
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 676
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 289
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

`max_jitter()`

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 213
def max_jitter
  (@config[:pool_jitter] || 0.2).to_f.clamp(MAX_JITTER)
end

🔎 See on GitHub

`pool=(value)`

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 50
def pool=(value)
  return if value.eql?(@pool)
  @schema_cache = nil
  @pool = value
end

🔎 See on GitHub

`pool_jitter(duration)`

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 324
def pool_jitter(duration)
  duration * (1.0 - @pool_jitter)
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 447
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 252
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 245
def preventing_writes?
  return true if replica?
  return false if connection_descriptor.nil?

  connection_descriptor.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 860
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 711
def reconnect!(restore_transactions: false)
  retries_available = connection_retries
  deadline = retry_deadline && Process.clock_gettime(Process::CLOCK_MONOTONIC) + retry_deadline

  @lock.synchronize do
    @allow_preconnect = false

    reconnect

    enable_lazy_transactions!
    @raw_connection_dirty = false
    @last_activity = @connected_since = Process.clock_gettime(Process::CLOCK_MONOTONIC)
    @verified = true
    @allow_preconnect = true

    reset_transaction(restore: restore_transactions) do
      clear_cache!(new_connection: true)
      attempt_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

    @last_activity = nil
    @verified = false

    raise translated_exception
  end
end

🔎 See on GitHub

`replica?()`

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 217
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 805
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 779
def reset!
  clear_cache!(new_connection: true)
  reset_transaction
  attempt_configure_connection
end

🔎 See on GitHub

`retry_deadline()`

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 229
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 310
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 431
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 320
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 927
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 316
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 440
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 420
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 512
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 547
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 552
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 571
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 595
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 537
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 416
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 507
def supports_deferrable_constraints?
  false
end

🔎 See on GitHub

`supports_disabling_indexes?()`

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 603
def supports_disabling_indexes?
  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 517
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 476
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 471
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 486
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 497
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 562
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 466
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 456
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 492
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 591
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 583
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 587
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 579
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 542
def supports_json?
  false
end

🔎 See on GitHub

`supports_lazy_transactions?()`

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 575
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 532
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 599
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 567
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 461
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 451
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 435
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 425
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 481
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 522
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 502
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 527
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 557
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 786
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 389
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 812
def verify!
  unless active?
    @lock.synchronize do
      if @unconfigured_connection
        @raw_connection = @unconfigured_connection
        @unconfigured_connection = nil
        attempt_configure_connection
        @last_activity = Process.clock_gettime(Process::CLOCK_MONOTONIC)
        @verified = true
        @allow_preconnect = true
        return
      end

      reconnect!(restore_transactions: true)
    end
  end

  @last_activity = Process.clock_gettime(Process::CLOCK_MONOTONIC)
  @verified = true
end

🔎 See on GitHub

`verify_timeout()`

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 225
def verify_timeout
  (@config[:verify_timeout] || 2).to_i
end

🔎 See on GitHub

Instance Private methods

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

📝 Source code

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 1200
def log(sql, name = "SQL", binds = [], type_casted_binds = [], async: false, allow_retry: false, &block) # :doc:
  instrumenter.instrument(
    "sql.active_record",
    sql:               sql,
    name:              name,
    binds:             binds,
    type_casted_binds: type_casted_binds,
    async:             async,
    allow_retry:       allow_retry,
    connection:        self,
    transaction:       current_transaction.user_transaction.presence,
    affected_rows:     0,
    row_count:         0,
    &block
  )
rescue ActiveRecord::StatementInvalid => ex
  raise ex.set_query(sql, binds)
end

🔎 See on GitHub

Definition files

activerecord/lib/active_record/connection_adapters/abstract_adapter.rb

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, **)

extensions()

index_algorithms()

lease()

max_jitter()

pool=(value)

pool_jitter(duration)

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_disabling_indexes?()

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?()

`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)`

`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, **)`

`extensions()`

`index_algorithms()`

`lease()`

`max_jitter()`

`pool=(value)`

`pool_jitter(duration)`

`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_disabling_indexes?()`

`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?()`