Class: ActiveRecord::ConnectionAdapters::AbstractAdapter

Inherits:
Object
  • Object
show all
Includes:
DatabaseLimits, DatabaseStatements, QueryCache, Quoting, Savepoints, SchemaStatements, ActiveSupport::Callbacks
Defined in:
activerecord/lib/active_record/connection_adapters/abstract_adapter.rb

Overview

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.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.

Direct Known Subclasses

AbstractMysqlAdapter

Defined Under Namespace

Classes: Version

Constant Summary collapse

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

Constants included from ActiveSupport::Callbacks

ActiveSupport::Callbacks::CALLBACK_FILTER_TYPES

Instance Attribute Summary collapse

Attributes included from QueryCache

#query_cache, #query_cache_enabled

Attributes included from DatabaseStatements

#transaction_manager

Class Method Summary collapse

Instance Method Summary collapse

Methods included from Savepoints

#create_savepoint, #current_savepoint_name, #exec_rollback_to_savepoint, #release_savepoint

Methods included from QueryCache

#cache, #clear_query_cache, dirties_query_cache, #disable_query_cache!, #enable_query_cache!, included, #select_all, #uncached

Methods included from DatabaseLimits

#index_name_length, #max_identifier_length, #table_alias_length, #table_name_length

Methods included from Quoting

#cast_bound_value, #column_name_matcher, #column_name_with_order_matcher, #lookup_cast_type_from_column, #quote, #quote_bound_value, #quote_column_name, #quote_default_expression, #quote_string, #quote_table_name, #quote_table_name_for_assignment, #quoted_binary, #quoted_date, #quoted_false, #quoted_time, #quoted_true, #sanitize_as_sql_comment, #type_cast, #unquoted_false, #unquoted_true

Methods included from DatabaseStatements

#add_transaction_record, #begin_db_transaction, #begin_isolated_db_transaction, #cacheable_query, #commit_db_transaction, #default_sequence_name, #delete, #empty_insert_statement_value, #exec_delete, #exec_insert, #exec_insert_all, #exec_query, #exec_restart_db_transaction, #exec_rollback_db_transaction, #exec_update, #execute, #explain, #high_precision_current_timestamp, #insert, #insert_fixture, #insert_fixtures_set, #mark_transaction_written_if_write, #query, #query_value, #query_values, #reset_sequence!, #reset_transaction, #restart_db_transaction, #rollback_db_transaction, #rollback_to_savepoint, #sanitize_limit, #select_all, #select_one, #select_rows, #select_value, #select_values, #to_sql, #transaction, #transaction_isolation_levels, #transaction_open?, #truncate, #truncate_tables, #update, #with_yaml_fallback, #write_query?

Methods included from SchemaStatements

#add_check_constraint, #add_column, #add_columns, #add_foreign_key, #add_index, #add_index_options, #add_reference, #add_timestamps, #assume_migrated_upto_version, #build_add_column_definition, #build_change_column_default_definition, #build_create_index_definition, #build_create_join_table_definition, #build_create_table_definition, #bulk_change_table, #change_column, #change_column_comment, #change_column_default, #change_column_null, #change_table, #change_table_comment, #check_constraint_exists?, #check_constraint_options, #check_constraints, #column_exists?, #columns, #columns_for_distinct, #create_join_table, #create_schema_dumper, #create_table, #data_source_exists?, #data_sources, #distinct_relation_for_primary_key, #drop_join_table, #drop_table, #dump_schema_information, #foreign_key_column_for, #foreign_key_exists?, #foreign_key_options, #foreign_keys, #index_algorithm, #index_exists?, #index_name, #index_name_exists?, #indexes, #internal_string_options_for_primary_key, #max_index_name_size, #native_database_types, #options_include_default?, #primary_key, #quoted_columns_for_index, #remove_check_constraint, #remove_column, #remove_columns, #remove_foreign_key, #remove_index, #remove_reference, #remove_timestamps, #rename_column, #rename_index, #rename_table, #schema_creation, #table_alias_for, #table_comment, #table_exists?, #table_options, #tables, #type_to_sql, #update_table_definition, #use_foreign_keys?, #valid_column_definition_options, #valid_primary_key_options, #valid_table_definition_options, #view_exists?, #views

Methods included from ActiveSupport::Callbacks

#run_callbacks

Methods included from ActiveSupport::Concern

#append_features, #class_methods, extended, #included, #prepend_features, #prepended

Constructor Details

#initialize(config_or_deprecated_connection, deprecated_logger = nil, deprecated_connection_options = nil, deprecated_config = nil) ⇒ AbstractAdapter

:nodoc:



126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 126

def initialize(config_or_deprecated_connection, deprecated_logger = nil, deprecated_connection_options = nil, deprecated_config = nil) # :nodoc:
  super()

  @raw_connection = nil
  @unconfigured_connection = nil

  if config_or_deprecated_connection.is_a?(Hash)
    @config = config_or_deprecated_connection.symbolize_keys
    @logger = ActiveRecord::Base.logger

    if deprecated_logger || deprecated_connection_options || deprecated_config
      raise ArgumentError, "when initializing an ActiveRecord adapter with a config hash, that should be the only argument"
    end
  else
    # Soft-deprecated for now; we'll probably warn in future.

    @unconfigured_connection = config_or_deprecated_connection
    @logger = deprecated_logger || ActiveRecord::Base.logger
    if deprecated_config
      @config = (deprecated_config || {}).symbolize_keys
      @connection_parameters = deprecated_connection_options
    else
      @config = (deprecated_connection_options || {}).symbolize_keys
      @connection_parameters = nil
    end
  end

  @owner = nil
  @instrumenter = ActiveSupport::Notifications.instrumenter
  @pool = ActiveRecord::ConnectionAdapters::NullPool.new
  @idle_since = Process.clock_gettime(Process::CLOCK_MONOTONIC)
  @visitor = arel_visitor
  @statements = build_statement_pool
  self.lock_thread = nil

  @prepared_statements = self.class.type_cast_config_to_boolean(
    @config.fetch(:prepared_statements) { default_prepared_statements }
  )

  @advisory_locks_enabled = self.class.type_cast_config_to_boolean(
    @config.fetch(:advisory_locks, true)
  )

  @default_timezone = self.class.validate_default_timezone(@config[:default_timezone])

  @raw_connection_dirty = false
  @verified = false
end

Instance Attribute Details

#lock ⇒ Object (readonly)

Returns the value of attribute lock



43
44
45
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 43

def lock
  @lock
end

#logger ⇒ Object (readonly)

Returns the value of attribute logger



43
44
45
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 43

def logger
  @logger
end

#owner ⇒ Object (readonly) Also known as: in_use?

Returns the value of attribute owner



43
44
45
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 43

def owner
  @owner
end

#pool ⇒ Object

Returns the value of attribute pool



42
43
44
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 42

def pool
  @pool
end

#visitor ⇒ Object (readonly)

Returns the value of attribute visitor



43
44
45
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 43

def visitor
  @visitor
end

Class Method Details

.build_read_query_regexp(*parts) ⇒ Object

:nodoc:



79
80
81
82
83
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 79

def self.build_read_query_regexp(*parts) # :nodoc:
  parts += DEFAULT_READ_QUERY
  parts = parts.map { |part| /#{part}/i }
  /\A(?:[(\s]|#{COMMENT_REGEX})*#{Regexp.union(*parts)}/
end

.database_exists?(config) ⇒ Boolean

Does the database for this adapter exist?

Returns:

  • (Boolean) 


385
386
387
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 385

def self.database_exists?(config)
  new(config).database_exists?
end

.dbconsole(config, options = {}) ⇒ Object

Opens a database console session.

Raises:

  • (NotImplementedError) 


122
123
124
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 122

def self.dbconsole(config, options = {})
  raise NotImplementedError
end

.extended_type_map(default_timezone:) ⇒ Object

:nodoc:



868
869
870
871
872
873
874
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 868

def extended_type_map(default_timezone:) # :nodoc:
  Type::TypeMap.new(self::TYPE_MAP).tap do |m|
    register_class_with_precision m, %r(\A[^\(]*time)i, Type::Time, timezone: default_timezone
    register_class_with_precision m, %r(\A[^\(]*datetime)i, Type::DateTime, timezone: default_timezone
    m.alias_type %r(\A[^\(]*timestamp)i, "datetime"
  end
end

.find_cmd_and_exec(commands, *args) ⇒ Object

:doc:



93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
 
# 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

.quoted_column_names ⇒ Object

:nodoc:



85
86
87
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 85

def self.quoted_column_names # :nodoc:
  @quoted_column_names ||= {}
end

.quoted_table_names ⇒ Object

:nodoc:



89
90
91
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 89

def self.quoted_table_names # :nodoc:
  @quoted_table_names ||= {}
end

.register_class_with_precision(mapping, key, klass, **kwargs) ⇒ Object

:nodoc:



861
862
863
864
865
866
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 861

def register_class_with_precision(mapping, key, klass, **kwargs) # :nodoc:
  mapping.register_type(key) do |*args|
    precision = extract_precision(args.last)
    klass.new(precision: precision, **kwargs)
  end
end

.type_cast_config_to_boolean(config) ⇒ Object 



58
59
60
61
62
63
64
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 58

def self.type_cast_config_to_boolean(config)
  if config == "false"
    false
  else
    config
  end
end

.type_cast_config_to_integer(config) ⇒ Object 



48
49
50
51
52
53
54
55
56
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 48

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

.validate_default_timezone(config) ⇒ Object 



66
67
68
69
70
71
72
73
74
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 66

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

Instance Method Details

#active? ⇒ Boolean

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.

Returns:

  • (Boolean) 


647
648
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 647

def active?
end

#adapter_name ⇒ Object

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



380
381
382
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 380

def adapter_name
  self.class::ADAPTER_NAME
end

#advisory_locks_enabled? ⇒ Boolean

:nodoc:

Returns:

  • (Boolean) 


602
603
604
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 602

def advisory_locks_enabled? # :nodoc:
  supports_advisory_locks? && @advisory_locks_enabled
end

#all_foreign_keys_valid? ⇒ Boolean

Override to check all foreign key constraints in a database.

Returns:

  • (Boolean) 


638
639
640
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 638

def all_foreign_keys_valid?
  true
end

#async_enabled? ⇒ Boolean

:nodoc:

Returns:

  • (Boolean) 


581
582
583
584
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 581

def async_enabled? # :nodoc:
  supports_concurrent_connections? &&
    !ActiveRecord.async_query_executor.nil? && !pool.async_executor.nil?
end

#build_insert_sql(insert) ⇒ Object

Called by ActiveRecord::InsertAll, Passed an instance of ActiveRecord::InsertAll::Builder, This method implements standard bulk inserts for all databases, but should be overridden by adapters to implement common features with non-standard syntax like handling duplicates or returning values.



834
835
836
837
838
839
840
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 834

def build_insert_sql(insert) # :nodoc:
  if insert.skip_duplicates? || insert.update_duplicates?
    raise NotImplementedError, "#{self.class} should define `build_insert_sql` to implement adapter-specific logic for handling duplicates during INSERT"
  end

  "INSERT #{insert.into} #{insert.values_list}"
end

#case_insensitive_comparison(attribute, value) ⇒ Object

:nodoc:



805
806
807
808
809
810
811
812
813
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 805

def case_insensitive_comparison(attribute, value) # :nodoc:
  column = column_for_attribute(attribute)

  if can_perform_case_insensitive_comparison_for?(column)
    attribute.lower.eq(attribute.relation.lower(value))
  else
    attribute.eq(value)
  end
end

#case_sensitive_comparison(attribute, value) ⇒ Object

:nodoc:



801
802
803
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 801

def case_sensitive_comparison(attribute, value) # :nodoc:
  attribute.eq(value)
end

#check_if_write_query(sql) ⇒ Object

:nodoc:



206
207
208
209
210
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 206

def check_if_write_query(sql) # :nodoc:
  if preventing_writes? && write_query?(sql)
    raise ActiveRecord::ReadOnlyError, "Write query attempted while in readonly mode: #{sql}"
  end
end

#check_version ⇒ Object

:nodoc:



849
850
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 849

def check_version # :nodoc:
end

#clean! ⇒ Object

:nodoc:



778
779
780
781
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 778

def clean! # :nodoc:
  @raw_connection_dirty = false
  @verified = nil
end

#clear_cache!(new_connection: false) ⇒ Object

Clear any caching the database adapter may be doing.



733
734
735
736
737
738
739
740
741
742
743
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 733

def clear_cache!(new_connection: false)
  if @statements
    @lock.synchronize do
      if new_connection
        @statements.reset
      else
        @statements.clear
      end
    end
  end
end

#close ⇒ Object

Check the connection back in to the connection pool



821
822
823
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 821

def close
  pool.checkin self
end

#connect! ⇒ Object 



773
774
775
776
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 773

def connect!
  verify!
  self
end

#connection_class ⇒ Object

:nodoc:



311
312
313
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 311

def connection_class # :nodoc:
  @pool.connection_class
end

#connection_retries ⇒ Object 



220
221
222
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 220

def connection_retries
  (@config[:connection_retries] || 1).to_i
end

#create_enum ⇒ Object

This is meant to be implemented by the adapters that support custom enum types



595
596
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 595

def create_enum(*) # :nodoc:
end

#database_exists? ⇒ Boolean

Returns:

  • (Boolean) 


389
390
391
392
393
394
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 389

def database_exists?
  connect!
  true
rescue ActiveRecord::NoDatabaseError
  false
end

#database_version ⇒ Object

:nodoc:



845
846
847
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 845

def database_version # :nodoc:
  schema_cache.database_version
end

#default_index_type?(index) ⇒ Boolean

:nodoc:

Returns:

  • (Boolean) 


825
826
827
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 825

def default_index_type?(index) # :nodoc:
  index.using.nil?
end

#default_timezone ⇒ Object 



232
233
234
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 232

def default_timezone
  @default_timezone || ActiveRecord.default_timezone
end

#default_uniqueness_comparison(attribute, value) ⇒ Object

:nodoc:



797
798
799
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 797

def default_uniqueness_comparison(attribute, value) # :nodoc:
  attribute.eq(value)
end

#disable_extension(name) ⇒ Object

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



587
588
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 587

def disable_extension(name, **)
end

#disable_referential_integrity ⇒ Object

Override to turn off referential integrity while executing &block.



633
634
635
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 633

def disable_referential_integrity
  yield
end

#discard! ⇒ Object

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.



702
703
704
705
706
707
708
709
710
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 702

def discard!
  # This should be overridden by concrete adapters.
  #
  # Prevent @raw_connection's finalizer from touching the socket, or
  # otherwise communicating with its server, when it is collected.
  if schema_cache.connection == self
    schema_cache.connection = nil
  end
end

#disconnect! ⇒ Object

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



690
691
692
693
694
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 690

def disconnect!
  clear_cache!(new_connection: true)
  reset_transaction
  @raw_connection_dirty = false
end

#drop_enum ⇒ Object

This is meant to be implemented by the adapters that support custom enum types



599
600
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 599

def drop_enum(*) # :nodoc:
end

#enable_extension(name) ⇒ Object

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



591
592
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 591

def enable_extension(name, **)
end

#expire ⇒ Object

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



337
338
339
340
341
342
343
344
345
346
347
348
349
350
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 337

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

#extensions ⇒ Object

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



621
622
623
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 621

def extensions
  []
end

#get_advisory_lock(lock_id) ⇒ Object

This is meant to be implemented by the adapters that support advisory locks

Return true if we got the lock, otherwise false



610
611
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 610

def get_advisory_lock(lock_id) # :nodoc:
end

#get_database_version ⇒ Object

:nodoc:



842
843
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 842

def get_database_version # :nodoc:
end

#index_algorithms ⇒ Object

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



626
627
628
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 626

def index_algorithms
  {}
end

#internal_metadata ⇒ Object

:nodoc:



259
260
261
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 259

def internal_metadata # :nodoc:
  InternalMetadata.new(self)
end

#lease ⇒ Object

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



296
297
298
299
300
301
302
303
304
305
306
307
308
309
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 296

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

#lock_thread=(lock_thread) ⇒ Object

:nodoc:



181
182
183
184
185
186
187
188
189
190
191
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 181

def lock_thread=(lock_thread) # :nodoc:
  @lock =
  case lock_thread
  when Thread
    THREAD_LOCK
  when Fiber
    FIBER_LOCK
  else
    ActiveSupport::Concurrency::NullLock
  end
end

#migration_context ⇒ Object

:nodoc:



251
252
253
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 251

def migration_context # :nodoc:
  MigrationContext.new(migrations_paths, schema_migration, internal_metadata)
end

#migrations_paths ⇒ Object

:nodoc:



247
248
249
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 247

def migrations_paths # :nodoc:
  @config[:migrations_paths] || Migrator.migrations_paths
end

#prefetch_primary_key?(table_name = nil) ⇒ Boolean

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.

Returns:

  • (Boolean) 


429
430
431
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 429

def prefetch_primary_key?(table_name = nil)
  false
end

#prepared_statements? ⇒ Boolean Also known as: prepared_statements

Returns:

  • (Boolean) 


263
264
265
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 263

def prepared_statements?
  @prepared_statements && !prepared_statements_disabled_cache.include?(object_id)
end

#prepared_statements_disabled_cache ⇒ Object

:nodoc:



268
269
270
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 268

def prepared_statements_disabled_cache # :nodoc:
  ActiveSupport::IsolatedExecutionState[:active_record_prepared_statements_disabled_cache] ||= Set.new
end

#preventing_writes? ⇒ Boolean

Determines whether writes are currently being prevented.

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

Returns:

  • (Boolean) 


240
241
242
243
244
245
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 240

def preventing_writes?
  return true if replica?
  return false if connection_class.nil?

  connection_class.current_preventing_writes
end

#raw_connection ⇒ Object

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.



789
790
791
792
793
794
795
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 789

def raw_connection
  with_raw_connection do |conn|
    disable_lazy_transactions!
    @raw_connection_dirty = true
    conn
  end
end

#reconnect!(restore_transactions: false) ⇒ Object

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



653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 653

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

#release_advisory_lock(lock_id) ⇒ Object

This is meant to be implemented by the adapters that support advisory locks.

Return true if we released the lock, otherwise false



617
618
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 617

def release_advisory_lock(lock_id) # :nodoc:
end

#replica? ⇒ Boolean

Returns:

  • (Boolean) 


212
213
214
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 212

def replica?
  @config[:replica] || false
end

#requires_reloading? ⇒ Boolean

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

Returns:

  • (Boolean) 


746
747
748
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 746

def requires_reloading?
  false
end

#reset! ⇒ Object

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).



720
721
722
723
724
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 720

def reset!
  clear_cache!(new_connection: true)
  reset_transaction
  configure_connection
end

#retry_deadline ⇒ Object 



224
225
226
227
228
229
230
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 224

def retry_deadline
  if @config[:retry_deadline]
    @config[:retry_deadline].to_f
  else
    nil
  end
end

#role ⇒ Object

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



317
318
319
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 317

def role
  @pool.role
end

#savepoint_errors_invalidate_transactions? ⇒ Boolean

Do TransactionRollbackErrors on savepoints affect the parent transaction?

Returns:

  • (Boolean) 


413
414
415
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 413

def savepoint_errors_invalidate_transactions?
  false
end

#schema_cache ⇒ Object 



327
328
329
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 327

def schema_cache
  @pool.get_schema_cache(self)
end

#schema_cache=(cache) ⇒ Object 



331
332
333
334
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 331

def schema_cache=(cache)
  cache.connection = self
  @pool.set_schema_cache(cache)
end

#schema_migration ⇒ Object

:nodoc:



255
256
257
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 255

def schema_migration # :nodoc:
  SchemaMigration.new(self)
end

#schema_version ⇒ Object

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.



856
857
858
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 856

def schema_version
  migration_context.current_version
end

#seconds_idle ⇒ Object

Seconds since this connection was returned to the pool



366
367
368
369
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 366

def seconds_idle # :nodoc:
  return 0 if in_use?
  Process.clock_gettime(Process::CLOCK_MONOTONIC) - @idle_since
end

#shard ⇒ Object

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



323
324
325
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 323

def shard
  @pool.shard
end

#steal! ⇒ Object

this method must only be called while holding connection pool’s mutex (and a desire for segfaults)



353
354
355
356
357
358
359
360
361
362
363
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 353

def steal! # :nodoc:
  if in_use?
    if @owner != ActiveSupport::IsolatedExecutionState.context
      pool.send :remove_connection_from_thread_cache, self, @owner

      @owner = ActiveSupport::IsolatedExecutionState.context
    end
  else
    raise ActiveRecordError, "Cannot steal connection, it is not currently leased."
  end
end

#supports_advisory_locks? ⇒ Boolean

Does this adapter support application-enforced advisory locking?

Returns:

  • (Boolean) 


422
423
424
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 422

def supports_advisory_locks?
  false
end

#supports_bulk_alter? ⇒ Boolean

Returns:

  • (Boolean) 


402
403
404
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 402

def supports_bulk_alter?
  false
end

#supports_check_constraints? ⇒ Boolean

Does this adapter support creating check constraints?

Returns:

  • (Boolean) 


494
495
496
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 494

def supports_check_constraints?
  false
end

#supports_comments? ⇒ Boolean

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

Returns:

  • (Boolean) 


529
530
531
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 529

def supports_comments?
  false
end

#supports_comments_in_create? ⇒ Boolean

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

Returns:

  • (Boolean) 


534
535
536
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 534

def supports_comments_in_create?
  false
end

#supports_common_table_expressions? ⇒ Boolean

Returns:

  • (Boolean) 


553
554
555
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 553

def supports_common_table_expressions?
  false
end

#supports_concurrent_connections? ⇒ Boolean

Returns:

  • (Boolean) 


577
578
579
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 577

def supports_concurrent_connections?
  true
end

#supports_datetime_with_precision? ⇒ Boolean

Does this adapter support datetime with precision?

Returns:

  • (Boolean) 


519
520
521
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 519

def supports_datetime_with_precision?
  false
end

#supports_ddl_transactions? ⇒ Boolean

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

Returns:

  • (Boolean) 


398
399
400
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 398

def supports_ddl_transactions?
  false
end

#supports_deferrable_constraints? ⇒ Boolean

Does this adapter support creating deferrable constraints?

Returns:

  • (Boolean) 


489
490
491
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 489

def supports_deferrable_constraints?
  false
end

#supports_exclusion_constraints? ⇒ Boolean

Does this adapter support creating exclusion constraints?

Returns:

  • (Boolean) 


499
500
501
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 499

def supports_exclusion_constraints?
  false
end

#supports_explain? ⇒ Boolean

Does this adapter support explain?

Returns:

  • (Boolean) 


458
459
460
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 458

def supports_explain?
  false
end

#supports_expression_index? ⇒ Boolean

Does this adapter support expression indices?

Returns:

  • (Boolean) 


453
454
455
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 453

def supports_expression_index?
  false
end

#supports_extensions? ⇒ Boolean

Does this adapter support database extensions?

Returns:

  • (Boolean) 


468
469
470
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 468

def supports_extensions?
  false
end

#supports_foreign_keys? ⇒ Boolean

Does this adapter support creating foreign key constraints?

Returns:

  • (Boolean) 


479
480
481
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 479

def supports_foreign_keys?
  false
end

#supports_foreign_tables? ⇒ Boolean

Does this adapter support foreign/external tables?

Returns:

  • (Boolean) 


544
545
546
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 544

def supports_foreign_tables?
  false
end

#supports_index_include? ⇒ Boolean

Does this adapter support including non-key columns?

Returns:

  • (Boolean) 


448
449
450
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 448

def supports_index_include?
  false
end

#supports_index_sort_order? ⇒ Boolean

Does this adapter support index sort order?

Returns:

  • (Boolean) 


438
439
440
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 438

def supports_index_sort_order?
  false
end

#supports_indexes_in_create? ⇒ Boolean

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

Returns:

  • (Boolean) 


474
475
476
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 474

def supports_indexes_in_create?
  false
end

#supports_insert_conflict_target? ⇒ Boolean

Returns:

  • (Boolean) 


573
574
575
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 573

def supports_insert_conflict_target?
  false
end

#supports_insert_on_duplicate_skip? ⇒ Boolean

Returns:

  • (Boolean) 


565
566
567
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 565

def supports_insert_on_duplicate_skip?
  false
end

#supports_insert_on_duplicate_update? ⇒ Boolean

Returns:

  • (Boolean) 


569
570
571
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 569

def supports_insert_on_duplicate_update?
  false
end

#supports_insert_returning? ⇒ Boolean

Returns:

  • (Boolean) 


561
562
563
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 561

def supports_insert_returning?
  false
end

#supports_json? ⇒ Boolean

Does this adapter support JSON data type?

Returns:

  • (Boolean) 


524
525
526
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 524

def supports_json?
  false
end

#supports_lazy_transactions? ⇒ Boolean

Returns:

  • (Boolean) 


557
558
559
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 557

def supports_lazy_transactions?
  false
end

#supports_materialized_views? ⇒ Boolean

Does this adapter support materialized views?

Returns:

  • (Boolean) 


514
515
516
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 514

def supports_materialized_views?
  false
end

#supports_optimizer_hints? ⇒ Boolean

Does this adapter support optimizer hints?

Returns:

  • (Boolean) 


549
550
551
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 549

def supports_optimizer_hints?
  false
end

#supports_partial_index? ⇒ Boolean

Does this adapter support partial indices?

Returns:

  • (Boolean) 


443
444
445
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 443

def supports_partial_index?
  false
end

#supports_partitioned_indexes? ⇒ Boolean

Returns:

  • (Boolean) 


433
434
435
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 433

def supports_partitioned_indexes?
  false
end

#supports_restart_db_transaction? ⇒ Boolean

Returns:

  • (Boolean) 


417
418
419
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 417

def supports_restart_db_transaction?
  false
end

#supports_savepoints? ⇒ Boolean

Does this adapter support savepoints?

Returns:

  • (Boolean) 


407
408
409
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 407

def supports_savepoints?
  false
end

#supports_transaction_isolation? ⇒ Boolean

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

Returns:

  • (Boolean) 


463
464
465
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 463

def supports_transaction_isolation?
  false
end

#supports_unique_keys? ⇒ Boolean

Does this adapter support creating unique constraints?

Returns:

  • (Boolean) 


504
505
506
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 504

def supports_unique_keys?
  false
end

#supports_validate_constraints? ⇒ Boolean

Does this adapter support creating invalid constraints?

Returns:

  • (Boolean) 


484
485
486
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 484

def supports_validate_constraints?
  false
end

#supports_views? ⇒ Boolean

Does this adapter support views?

Returns:

  • (Boolean) 


509
510
511
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 509

def supports_views?
  false
end

#supports_virtual_columns? ⇒ Boolean

Does this adapter support virtual columns?

Returns:

  • (Boolean) 


539
540
541
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 539

def supports_virtual_columns?
  false
end

#throw_away! ⇒ Object

Removes the connection from the pool and disconnect it.



727
728
729
730
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 727

def throw_away!
  pool.remove self
  disconnect!
end

#unprepared_statement ⇒ Object 



371
372
373
374
375
376
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 371

def unprepared_statement
  cache = prepared_statements_disabled_cache.add?(object_id) if @prepared_statements
  yield
ensure
  cache&.delete(object_id)
end

#use_metadata_table? ⇒ Boolean

Returns:

  • (Boolean) 


216
217
218
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 216

def use_metadata_table?
  @config.fetch(:use_metadata_table, true)
end

#valid_type?(type) ⇒ Boolean

:nodoc:

Returns:

  • (Boolean) 


291
292
293
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 291

def valid_type?(type) # :nodoc:
  !native_database_types[type].nil?
end

#verify! ⇒ Object

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.



753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 753

def verify!
  unless active?
    if @unconfigured_connection
      @lock.synchronize do
        if @unconfigured_connection
          @raw_connection = @unconfigured_connection
          @unconfigured_connection = nil
          configure_connection
          @verified = true
          return
        end
      end
    end

    reconnect!(restore_transactions: true)
  end

  @verified = true
end

#with_instrumenter(instrumenter, &block) ⇒ Object

:nodoc:



196
197
198
199
200
201
202
203
204
 
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 196

def with_instrumenter(instrumenter, &block) # :nodoc:
  Thread.handle_interrupt(EXCEPTION_NEVER) do
    previous_instrumenter = @instrumenter
    @instrumenter = instrumenter
    Thread.handle_interrupt(EXCEPTION_IMMEDIATE, &block)
  ensure
    @instrumenter = previous_instrumenter
  end
end