Class: ActiveRecord::ConnectionAdapters::Mysql2Adapter

Relationships & Source Files
Super Chains via Extension / Inclusion / Inheritance
Class Chain: self, `AbstractMysqlAdapter`, `AbstractAdapter`, `::ActiveSupport::DescendantsTracker`
Instance Chain: self, `Mysql2::DatabaseStatements`, `AbstractMysqlAdapter`, `MySQL::SchemaStatements`, `MySQL::Quoting`, `MySQL::DatabaseStatements`, `AbstractAdapter`, `Savepoints`, `::ActiveRecord::QueryCache`, `DatabaseLimits`, `Quoting`, `DatabaseStatements`, `SchemaStatements`, `::ActiveRecord::Migration::JoinTable`, `::ActiveSupport::Callbacks`
Inherits:	ActiveRecord::ConnectionAdapters::AbstractMysqlAdapter `::Object` ActiveRecord::ConnectionAdapters::AbstractAdapter ActiveRecord::ConnectionAdapters::AbstractMysqlAdapter ActiveRecord::ConnectionAdapters::Mysql2Adapter
Defined in:	activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb

Overview

Active Record MySQL2 Adapter

Constant Summary

ADAPTER_NAME =
# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 19
```
"Mysql2"
```
ER_ACCESS_DENIED_ERROR =
# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 15
```
1045
```
ER_BAD_DB_ERROR =
# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 13
```
1049
```
ER_CONN_HOST_ERROR =
# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 16
```
2003
```
ER_DBACCESS_DENIED_ERROR =
# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 14
```
1044
```
ER_UNKNOWN_HOST_ERROR =
# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 17
```
2005
```
TYPE_MAP =
# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 53
```
Type::TypeMap.new.tap { |m| initialize_type_map(m) }
```

Class Attribute Summary

`AbstractMysqlAdapter` - Inherited

.emulate_booleans, .emulate_booleans?

`AbstractAdapter` - Inherited

.__callbacks

`AbstractMysqlAdapter` - Inherited

.dbconsole, .extract_precision, .initialize_type_map, .register_integer_type, .extended_type_map

`AbstractAdapter` - Inherited

.database_exists?	Does the database for this adapter exist?
.dbconsole	Opens a database console session.
.find_cmd_and_exec, .type_cast_config_to_boolean, .type_cast_config_to_integer, .validate_default_timezone, .extract_limit, .extract_precision, .extract_scale, .initialize_type_map, .register_class_with_limit, .build_read_query_regexp, .extended_type_map, .new, .register_class_with_precision

`::ActiveSupport::DescendantsTracker` - Inherited

descendants, subclasses, clear, disable_clear!, reject!

Instance Attribute Summary

#active? ⇒ Boolean readonly
#connected? ⇒ Boolean readonly
#savepoint_errors_invalidate_transactions? ⇒ Boolean readonly
#supports_comments? ⇒ Boolean readonly
#supports_comments_in_create? ⇒ Boolean readonly
#supports_json? ⇒ Boolean readonly
#supports_lazy_transactions? ⇒ Boolean readonly
#supports_savepoints? ⇒ Boolean readonly

`Mysql2::DatabaseStatements` - Included

#multi_statements_enabled?

`AbstractMysqlAdapter` - Inherited

#emulate_booleans, #emulate_booleans?, #strict_mode?, #supports_advisory_locks?, #supports_bulk_alter?, #supports_check_constraints?, #supports_common_table_expressions?, #supports_datetime_with_precision?, #supports_explain?, #supports_expression_index?, #supports_foreign_keys?, #supports_index_sort_order?, #supports_indexes_in_create?, #supports_insert_on_duplicate_skip?, #supports_insert_on_duplicate_update?, #supports_insert_returning?,
#supports_optimizer_hints?	See dev.mysql.com/doc/refman/en/optimizer-hints.html for more details.
#supports_restart_db_transaction?, #supports_transaction_isolation?, #supports_views?, #supports_virtual_columns?, #supports_insert_raw_alias_syntax?, #supports_rename_column?, #supports_rename_index?, #mariadb?

`MySQL::SchemaStatements` - Included

#row_format_dynamic_by_default?

`MySQL::DatabaseStatements` - Included

#analyze_without_explain?

mariadb.com/kb/en/analyze-statement/.

`AbstractAdapter` - Inherited

#__callbacks,
#active?	Checks whether the connection to the database is still active.
#connected?	Checks whether the connection to the database was established.
#database_exists?,
#in_use?	Alias for AbstractAdapter#owner.
#lock, #logger, #owner, #pool, #pool=,
#prepared_statements	Alias for AbstractAdapter#prepared_statements?.
#preventing_writes?	Determines whether writes are currently being prevented.
#replica?,
#requires_reloading?	Returns true if its required to reload the connection between requests for development mode.
#savepoint_errors_invalidate_transactions?	Do TransactionRollbackErrors on savepoints affect the parent transaction?
#supports_advisory_locks?	Does this adapter support application-enforced advisory locking?
#supports_bulk_alter?,
#supports_check_constraints?	Does this adapter support creating check constraints?
#supports_comments?	Does this adapter support metadata comments on database objects (tables, columns, indexes)?
#supports_comments_in_create?	Can comments for tables, columns, and indexes be specified in create/alter table statements?
#supports_common_table_expressions?, #supports_concurrent_connections?,
#supports_datetime_with_precision?	Does this adapter support datetime with precision?
#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?
#supports_deferrable_constraints?	Does this adapter support creating deferrable constraints?
#supports_exclusion_constraints?	Does this adapter support creating exclusion constraints?
#supports_explain?	Does this adapter support explain?
#supports_expression_index?	Does this adapter support expression indices?
#supports_extensions?	Does this adapter support database extensions?
#supports_foreign_keys?	Does this adapter support creating foreign key constraints?
#supports_foreign_tables?	Does this adapter support foreign/external tables?
#supports_index_include?	Does this adapter support including non-key columns?
#supports_index_sort_order?	Does this adapter support index sort order?
#supports_indexes_in_create?	Does this adapter support creating indexes in the same statement as creating the table?
#supports_insert_conflict_target?, #supports_insert_on_duplicate_skip?, #supports_insert_on_duplicate_update?, #supports_insert_returning?,
#supports_json?	Does this adapter support JSON data type?
#supports_lazy_transactions?,
#supports_materialized_views?	Does this adapter support materialized views?
#supports_nulls_not_distinct?,
#supports_optimizer_hints?	Does this adapter support optimizer hints?
#supports_partial_index?	Does this adapter support partial indices?
#supports_partitioned_indexes?, #supports_restart_db_transaction?,
#supports_savepoints?	Does this adapter support savepoints?
#supports_transaction_isolation?	Does this adapter support setting the isolation level for a transaction?
#supports_unique_constraints?	Does this adapter support creating unique constraints?
#supports_validate_constraints?	Does this adapter support creating invalid constraints?
#supports_views?	Does this adapter support views?
#supports_virtual_columns?	Does this adapter support virtual columns?
#visitor, #reconnect_can_restore_state?, #advisory_locks_enabled?, #async_enabled?, #lock_thread=

`DatabaseStatements` - Included

#begin_transaction, #commit_transaction, #current_transaction, #dirty_current_transaction, #materialize_transactions, #open_transactions, #rollback_transaction, #transaction_open?, #within_new_transaction, #transaction_manager

`SchemaStatements` - Included

#use_foreign_keys?, #foreign_keys_enabled?

Instance Method Summary

#disconnect!

Disconnects from the database if already connected.
#error_number(exception)

HELPER METHODS ===========================================.
#reset!
#configure_connection private
#connect private
#default_prepared_statements private
#full_version private
#get_full_version private
#reconnect private
#text_type?(type) ⇒ Boolean private
#translate_exception(exception, message:, sql:, binds:) private
#discard! Internal use only

`Mysql2::DatabaseStatements` - Included

#affected_rows, #cast_result, #execute_batch, #last_inserted_id, #perform_query,
#select_all	Returns an `::ActiveRecord::Result` instance.

`AbstractMysqlAdapter` - Inherited

#charset	Returns the database character set.
#check_constraints,
#collation	Returns the database collation strategy.
#create_database	Create a new `MySQL` database with optional `:charset` and `:collation`.
#current_database,
#drop_table	Drops a table or tables from the database.
#foreign_keys, #index_algorithms, #native_database_types,
#quote_string	Quotes strings for use in SQL input.
#recreate_database	Drops the database specified on the `name` attribute and creates it again using the provided `options`.
#rename_index,
#rename_table	Renames a table.
#show_variable	SHOW VARIABLES LIKE ‘name’.
#add_index_for_alter, #arel_visitor, #build_statement_pool, #can_perform_case_insensitive_comparison_for?, #change_column_for_alter, #configure_connection, #extended_type_map_key, #handle_warnings, #mismatched_foreign_key, #mismatched_foreign_key_details, #remove_index_for_alter, #rename_column_for_alter, #strip_whitespace_characters, #translate_exception, #version_string, #warning_ignored?, #add_index, #add_sql_comment!, #begin_db_transaction, #begin_isolated_db_transaction, #build_change_column_default_definition,
#build_change_column_definition	Builds a `ChangeColumnDefinition` object.
#build_create_index_definition, #build_insert_sql, #case_sensitive_comparison, #change_column, #change_column_comment, #change_column_default, #change_column_null, #change_table_comment, #check_version,
#columns_for_distinct	In MySQL 5.7.5 and up, ONLY_FULL_GROUP_BY affects handling of queries that use DISTINCT and ORDER BY.
#commit_db_transaction, #default_index_type?,
#disable_referential_integrity	REFERENTIAL INTEGRITY ====================================.
#drop_database	Drops a `MySQL` database.
#empty_insert_statement_value,
#error_number	Must return the `MySQL` error number from the exception, if the exception has an error number.
#exec_restart_db_transaction, #exec_rollback_db_transaction, #get_advisory_lock, #get_database_version, #primary_keys, #release_advisory_lock, #rename_column, #table_comment, #table_options, #column_definitions, #create_table_info

`MySQL::SchemaStatements` - Included

#create_schema_dumper, #create_table,
#indexes	Returns an array of indexes for the given table.
#internal_string_options_for_primary_key, #remove_column, #schema_creation, #table_alias_length,
#type_to_sql	Maps logical `::Rails` types to MySQL-specific data types.
#update_table_definition, #add_index_length, #add_options_for_index_columns, #create_table_definition, #data_source_sql, #default_row_format, #default_type, #extract_foreign_key_action, #extract_schema_qualified_name, #fetch_type_metadata, #integer_to_sql, #limit_to_size, #new_column_from_field, #quoted_scope, #type_with_size_to_sql, #valid_primary_key_options

`MySQL::Quoting` - Included

#cast_bound_value, #quoted_binary,
#type_cast	Override `type_cast` we pass to mysql2 `::Date` and `::Time` objects instead of Strings since `MySQL` adapters are able to handle those classes more efficiently.
#unquote_identifier, #unquoted_false, #unquoted_true

`MySQL::DatabaseStatements` - Included

#build_explain_clause, #explain, #high_precision_current_timestamp, #combine_multi_statements, #default_insert_value, #max_allowed_packet, #max_allowed_packet_reached?, #returning_column_values, #write_query?

`AbstractAdapter` - Inherited

#adapter_name	Returns the human-readable name of the adapter.
#check_all_foreign_keys_valid!	Override to check all foreign key constraints in a database.
#clear_cache!	Clear any caching the database adapter may be doing.
#close	Check the connection back in to the connection pool.
#connect!, #connection_retries, #default_timezone,
#disable_extension	This is meant to be implemented by the adapters that support extensions.
#disable_referential_integrity	Override to turn off referential integrity while executing `&block`.
#discard!	Immediately forget this connection ever existed.
#disconnect!	Disconnects from the database if already connected.
#enable_extension	This is meant to be implemented by the adapters that support extensions.
#expire	this method must only be called while holding connection pool’s mutex.
#extensions	A list of extensions, to be filled in by adapters that support them.
#index_algorithms	A list of index algorithms, to be filled by adapters that support them.
#lease	this method must only be called while holding connection pool’s mutex.
#prefetch_primary_key?	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.
#prepared_statements?,
#raw_connection	Provides access to the underlying database driver for this adapter.
#reconnect!	Disconnects from the database if already connected, and establishes a new connection with the database.
#reset!	Reset the state of this connection, directing the DBMS to clear transactions and other connection-related server-side state.
#retry_deadline,
#role	The role (e.g. `:writing`) for the current connection.
#schema_cache,
#schema_version	Returns the version identifier of the schema currently available in the database.
#shard	The shard (e.g. `:default`) for the current connection.
#throw_away!	Removes the connection from the pool and disconnect it.
#unprepared_statement,
#verify!	Checks whether the connection to the database is still active (i.e. not stale).
#any_raw_connection	Returns a raw connection for internal use with methods that are known to both be thread-safe and not rely upon actual server communication.
#arel_visitor, #backoff,
#build_result	Builds the result object.
#build_statement_pool, #can_perform_case_insensitive_comparison_for?, #collector, #column_for, #column_for_attribute,
#configure_connection	Perform any necessary initialization upon the newly-established connection settings, run queries to configure any application-global “session” variables, etc.
#default_prepared_statements, #extended_type_map_key, #invalidate_transaction, #log, #reconnect, #retryable_connection_error?, #retryable_query_error?, #translate_exception, #translate_exception_class, #type_map,
#valid_raw_connection	Similar to any_raw_connection, but ensures it is validated and connected.
#verified!	Mark the connection as verified.
#warning_ignored?,
#with_raw_connection	Lock the monitor, ensure we’re properly connected and transactions are materialized, and then yield the underlying raw connection object.
#add_enum_value	This is meant to be implemented by the adapters that support custom enum types.
#build_insert_sql	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.
#case_insensitive_comparison, #case_sensitive_comparison, #check_if_write_query, #check_version, #clean!, #connection_class,
#create_enum	This is meant to be implemented by the adapters that support custom enum types.
#create_virtual_table	This is meant to be implemented by the adapters that support virtual tables.
#database_version, #default_index_type?, #default_uniqueness_comparison,
#drop_enum	This is meant to be implemented by the adapters that support custom enum types.
#drop_virtual_table	This is meant to be implemented by the adapters that support virtual tables.
#get_advisory_lock	This is meant to be implemented by the adapters that support advisory locks.
#get_database_version, #inspect, #prepared_statements_disabled_cache,
#release_advisory_lock	This is meant to be implemented by the adapters that support advisory locks.
#rename_enum	This is meant to be implemented by the adapters that support custom enum types.
#rename_enum_value	This is meant to be implemented by the adapters that support custom enum types.
#return_value_after_insert?,
#seconds_idle	Seconds since this connection was returned to the pool.
#steal!	this method must only be called while holding connection pool’s mutex (and a desire for segfaults).
#valid_type?, #with_instrumenter

`Savepoints` - Included

#create_savepoint, #current_savepoint_name, #exec_rollback_to_savepoint, #release_savepoint

`DatabaseLimits` - Included

#index_name_length	Returns the maximum length of an index name.
#table_alias_length	Returns the maximum length of a table alias.
#table_name_length	Returns the maximum length of a table name.
#bind_params_length, #max_identifier_length

`Quoting` - Included

#quote	Quotes the column value to help prevent SQL injection attacks.
#quote_column_name	Quotes the column name.
#quote_string	Quotes a string, escaping any ‘ (single quote) and \ (backslash) characters.
#quote_table_name	Quotes the table name.
#quote_table_name_for_assignment	Override to return the quoted table name for assignment.
#quoted_date	Quote date/time values for use in SQL input.
#quoted_false, #quoted_true,
#type_cast	Cast a `value` to a type that the database understands.
#unquoted_false, #unquoted_true, #lookup_cast_type, #type_casted_binds,
#cast_bound_value	Cast a value to be used as a bound parameter of unknown type.
#lookup_cast_type_from_column	If you are having to call this function, you are likely doing something wrong.
#quote_default_expression, #quoted_binary, #quoted_time, #sanitize_as_sql_comment

`DatabaseStatements` - Included

#add_transaction_record	Register a record with the current transaction so that its after_commit and after_rollback callbacks can be called.
#begin_db_transaction	Begins the transaction (and turns off auto-committing).
#begin_isolated_db_transaction	Begins the transaction with the isolation level set.
#commit_db_transaction	Commits the transaction (and turns on auto-committing).
#create	Alias for DatabaseStatements#insert.
#default_sequence_name,
#delete	Executes the delete statement and returns the number of rows affected.
#disable_lazy_transactions!, #empty_insert_statement_value, #enable_lazy_transactions!,
#exec_delete	Executes delete `sql` statement in the context of this connection using `binds` as the bind substitutes.
#exec_insert	Executes insert `sql` statement in the context of this connection using `binds` as the bind substitutes.
#exec_query	Executes `sql` statement in the context of this connection using `binds` as the bind substitutes.
#exec_update	Executes update `sql` statement in the context of this connection using `binds` as the bind substitutes.
#execute	Executes the SQL statement in the context of this connection and returns the raw result from the connection adapter.
#high_precision_current_timestamp	Returns an `::Arel` SQL literal for the CURRENT_TIMESTAMP for usage with arbitrary precision date/time columns.
#initialize,
#insert	Executes an INSERT query and returns the new record’s ID.
#insert_fixture	Inserts the given fixture into the table.
#insert_fixtures_set,
#reset_isolation_level	Hook point called after an isolated DB transaction is committed or rolled back.
#reset_sequence!	Set the sequence to the max value of the table’s column.
#restart_db_transaction,
#rollback_db_transaction	Rolls back the transaction (and turns on auto-committing).
#rollback_to_savepoint,
#sanitize_limit	Sanitizes the given LIMIT parameter in order to prevent SQL injection.
#select_all	Returns an `::ActiveRecord::Result` instance.
#select_one	Returns a record hash with the column names as keys and column values as values.
#select_rows	Returns an array of arrays containing the field values.
#select_value	Returns a single value from a record.
#select_values	Returns an array of the values of the first column in a select:
#to_sql	Converts an arel AST to SQL.
#transaction	Runs the given block in a database transaction, and returns the result of the block.
#transaction_isolation_levels,
#truncate	Executes the truncate statement.
#update	Executes the update statement and returns the number of rows affected.
#write_query?	Determines whether the SQL statement is a write query.
#affected_rows, #arel_from_relation, #build_fixture_sql, #build_fixture_statements, #build_truncate_statement, #build_truncate_statements,
#cast_result	Receive a native adapter result object and returns an `::ActiveRecord::Result` object.
#combine_multi_statements, #default_insert_value, #execute_batch, #extract_table_ref_from_insert_sql,
#internal_execute	Same as `#internal_exec_query`, but yields a native adapter result.
#last_inserted_id, #perform_query, #preprocess_query,
#raw_execute	Lowest level way to execute a query.
#returning_column_values,
#select	Returns an `::ActiveRecord::Result` instance.
#single_value_from_rows, #begin_deferred_transaction,
#cacheable_query	This is used in the `::ActiveRecord::StatementCache` object.
#exec_insert_all, #exec_restart_db_transaction, #exec_rollback_db_transaction, #explain,
#internal_exec_query	Execute a query and returns an `::ActiveRecord::Result`
#mark_transaction_written_if_write, #query, #query_value, #query_values,
#raw_exec_query	Same as raw_execute but returns an `::ActiveRecord::Result` object.
#reset_transaction, #truncate_tables,
#with_yaml_fallback	`::ActiveRecord::Fixture` value is quoted by `::Arel`, however scalar values are not quotable.
#sql_for_insert, #to_sql_and_binds

`SchemaStatements` - Included

#add_belongs_to	Alias for SchemaStatements#add_reference.
#add_check_constraint	Adds a new check constraint to the table.
#add_column	Add a new `type` column named `column_name` to `table_name`.
#add_foreign_key	Adds a new foreign key.
#add_index	Adds a new index to the table.
#add_reference	Adds a reference.
#add_timestamps	Adds timestamps (`created_at` and `updated_at`) columns to `table_name`.
#assume_migrated_upto_version,
#build_create_table_definition	Returns a `TableDefinition` object containing information about the table that would be created if the same arguments were passed to `#create_table`.
#change_column	Changes the column’s definition according to the new options.
#change_column_comment	Changes the comment for a column or removes it if `nil`.
#change_column_default	Sets a new default value for a column:
#change_column_null	Sets or removes a `NOT NULL` constraint on a column.
#change_table	A block for changing columns in `table`.
#change_table_comment	Changes the comment for a table or removes it if `nil`.
#check_constraint_exists?	Checks to see if a check constraint exists on a table for a given check constraint definition.
#check_constraints	Returns an array of check constraints for the given table.
#column_exists?	Checks to see if a column exists in a given table.
#columns	Returns an array of `Column` objects for the table specified by `table_name`.
#create_join_table	Creates a new join table with the name created using the lexical order of the first two arguments.
#create_table	Creates a new table with the name `table_name`.
#data_source_exists?	Checks to see if the data source `name` exists on the database.
#data_sources	Returns the relation names usable to back Active Record models.
#drop_join_table	Drops the join table specified by the given arguments.
#drop_table	Drops a table or tables from the database.
#foreign_key_exists?	Checks to see if a foreign key exists on a table for a given foreign key definition.
#foreign_keys	Returns an array of foreign keys for the given table.
#index_exists?	Checks to see if an index exists on a table for a given index definition.
#index_name_exists?	Verifies the existence of an index with a given name.
#indexes	Returns an array of indexes for the given table.
#max_index_name_size	Returns the maximum length of an index name in bytes.
#native_database_types	Returns a hash of mappings from the abstract data types to the native database types.
#options_include_default?,
#primary_key	Returns just a table’s primary key.
#remove_belongs_to	Alias for SchemaStatements#remove_reference.
#remove_check_constraint	Removes the given check constraint from the table.
#remove_column	Removes the column from the table definition.
#remove_columns	Removes the given columns from the table definition.
#remove_foreign_key	Removes the given foreign key from the table.
#remove_index	Removes the given index from the table.
#remove_reference	Removes the reference(s).
#remove_timestamps	Removes the timestamp columns (`created_at` and `updated_at`) from the table definition.
#rename_column	Renames a column.
#rename_index	Renames an index.
#rename_table	Renames a table.
#table_alias_for	Truncates a table alias according to the limits of the current adapter.
#table_comment	Returns the table comment that’s stored in database metadata.
#table_exists?	Checks to see if the table `table_name` exists on the database.
#table_options,
#tables	Returns an array of table names defined in the database.
#view_exists?	Checks to see if the view `view_name` exists on the database.
#views	Returns an array of view names defined in the database.
#add_column_for_alter, #add_index_sort_order,
#add_options_for_index_columns	Overridden by the `MySQL` adapter for supporting index lengths and by the `PostgreSQL` adapter for supporting operator classes.
#add_timestamps_for_alter, #can_remove_index_by_name?, #change_column_default_for_alter, #check_constraint_for, #check_constraint_for!, #check_constraint_name, #column_options_keys, #create_alter_table, #create_table_definition, #data_source_sql,
#expression_column_name?	Try to identify whether the given column name is an expression.
#extract_foreign_key_action,
#extract_new_comment_value	Alias for SchemaStatements#extract_new_default_value.
#extract_new_default_value, #fetch_type_metadata, #foreign_key_for, #foreign_key_for!, #foreign_key_name, #generate_index_name, #index_column_names, #index_name_for_remove, #index_name_options, #insert_versions_sql, #options_for_index_columns, #quoted_scope, #reference_name_for_table, #remove_column_for_alter, #remove_columns_for_alter, #remove_timestamps_for_alter, #rename_column_indexes, #rename_column_sql, #rename_table_indexes, #strip_table_name_prefix_and_suffix, #validate_change_column_null_argument!, #validate_create_table_options!, #validate_index_length!, #validate_table_length!, #add_columns, #add_index_options,
#build_add_column_definition	Builds an `AlterTable` object for adding a column to a table.
#build_change_column_default_definition	Builds a `ChangeColumnDefaultDefinition` object.
#build_create_index_definition	Builds a `CreateIndexDefinition` object.
#build_create_join_table_definition	Builds a `TableDefinition` object for a join table.
#bulk_change_table, #check_constraint_options,
#columns_for_distinct	Given a set of columns and an ORDER BY clause, returns the columns for a SELECT DISTINCT.
#create_schema_dumper, #distinct_relation_for_primary_key, #dump_schema_information, #foreign_key_column_for, #foreign_key_options, #index_algorithm, #index_name, #internal_string_options_for_primary_key, #quoted_columns_for_index, #remove_constraint,
#schema_creation	Returns an instance of `SchemaCreation`, which can be used to visit a schema definition object and return DDL.
#type_to_sql, #update_table_definition, #valid_column_definition_options, #valid_primary_key_options, #valid_table_definition_options

`::ActiveRecord::Migration::JoinTable` - Included

#find_join_table_name, #join_table_name

`::ActiveSupport::Callbacks` - Included

#run_callbacks	Runs the callbacks for the given event.
#halted_callback_hook	A hook invoked every time a before callback is halted.

Constructor Details

.new ⇒ `Mysql2Adapter`

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 55


def initialize(...)
  super

  @affected_rows_before_warnings = nil
  @config[:flags] ||= 0

  if @config[:flags].kind_of? Array
    @config[:flags].push "FOUND_ROWS"
  else
    @config[:flags] |= ::Mysql2::Client::FOUND_ROWS
  end

  @connection_parameters ||= @config
end

Class Method Details

.initialize_type_map(m) (private)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 40


def initialize_type_map(m)
  super

  m.register_type(%r(char)i) do |sql_type|
    limit = extract_limit(sql_type)
    Type.lookup(:string, adapter: :mysql2, limit: limit)
  end

  m.register_type %r(^enum)i, Type.lookup(:string, adapter: :mysql2)
  m.register_type %r(^set)i,  Type.lookup(:string, adapter: :mysql2)
end

.new_client(config)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 24


def new_client(config)
  ::Mysql2::Client.new(config)
rescue ::Mysql2::Error => error
  case error.error_number
  when ER_BAD_DB_ERROR
    raise ActiveRecord::NoDatabaseError.db_error(config[:database])
  when ER_DBACCESS_DENIED_ERROR, ER_ACCESS_DENIED_ERROR
    raise ActiveRecord::DatabaseConnectionError.username_error(config[:username])
  when ER_CONN_HOST_ERROR, ER_UNKNOWN_HOST_ERROR
    raise ActiveRecord::DatabaseConnectionError.hostname_error(config[:host])
  else
    raise ActiveRecord::ConnectionNotEstablished, error.message
  end
end

Instance Attribute Details

#active? ⇒ `Boolean` (readonly)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 108


def active?
  connected? && @lock.synchronize { @raw_connection&.ping } || false
end

#connected? ⇒ `Boolean` (readonly)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 104


def connected?
  !(@raw_connection.nil? || @raw_connection.closed?)
end

#savepoint_errors_invalidate_transactions? ⇒ `Boolean` (readonly)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 86


def savepoint_errors_invalidate_transactions?
  true
end

#supports_comments? ⇒ `Boolean` (readonly)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 74


def supports_comments?
  true
end

#supports_comments_in_create? ⇒ `Boolean` (readonly)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 78


def supports_comments_in_create?
  true
end

#supports_json? ⇒ `Boolean` (readonly)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 70


def supports_json?
  !mariadb? && database_version >= "5.7.8"
end

#supports_lazy_transactions? ⇒ `Boolean` (readonly)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 90


def supports_lazy_transactions?
  true
end

#supports_savepoints? ⇒ `Boolean` (readonly)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 82


def supports_savepoints?
  true
end

Instance Method Details

#configure_connection (private)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 151


def configure_connection
  @raw_connection.query_options[:as] = :array
  @raw_connection.query_options[:database_timezone] = default_timezone
  super
end

#connect (private)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 137


def connect
  @raw_connection = self.class.new_client(@connection_parameters)
rescue ConnectionNotEstablished => ex
  raise ex.set_pool(@pool)
end

#default_prepared_statements (private)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 179


def default_prepared_statements
  false
end

#discard!

This method is for internal use only.

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 124


def discard! # :nodoc:
  @lock.synchronize do
    super
    @raw_connection&.automatic_close = false
    @raw_connection = nil
  end
end

#disconnect!

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

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 116


def disconnect!
  @lock.synchronize do
    super
    @raw_connection&.close
    @raw_connection = nil
  end
end

#error_number(exception)

HELPER METHODS ===========================================

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 96


def error_number(exception)
  exception.error_number if exception.respond_to?(:error_number)
end

#full_version (private)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 157


def full_version
  database_version.full_version_string
end

#get_full_version (private)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 161


def get_full_version
  any_raw_connection.server_info[:version]
end

#reconnect (private)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 143


def reconnect
  @lock.synchronize do
    @raw_connection&.close
    @raw_connection = nil
    connect
  end
end

#reset!

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 112


alias :reset! :reconnect!

#text_type?(type) ⇒ `Boolean` (private)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 133


def text_type?(type)
  TYPE_MAP.lookup(type).is_a?(Type::String) || TYPE_MAP.lookup(type).is_a?(Type::Text)
end

#translate_exception(exception, message:, sql:, binds:) (private)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb', line 165


def translate_exception(exception, message:, sql:, binds:)
  if exception.is_a?(::Mysql2::Error::TimeoutError) && !exception.error_number
    ActiveRecord::AdapterTimeout.new(message, sql: sql, binds: binds, connection_pool: @pool)
  elsif exception.is_a?(::Mysql2::Error::ConnectionError)
    if exception.message.match?(/MySQL client is not connected/i)
      ActiveRecord::ConnectionNotEstablished.new(exception, connection_pool: @pool)
    else
      ActiveRecord::ConnectionFailed.new(message, sql: sql, binds: binds, connection_pool: @pool)
    end
  else
    super
  end
end

Class: ActiveRecord::ConnectionAdapters::Mysql2Adapter

Overview

Active Record MySQL2 Adapter

Constant Summary

::ActiveSupport::Callbacks - Included

DatabaseStatements - Included

AbstractAdapter - Inherited

MySQL::DatabaseStatements - Included

MySQL::Quoting - Included

MySQL::SchemaStatements - Included

AbstractMysqlAdapter - Inherited

Class Attribute Summary

AbstractMysqlAdapter - Inherited

AbstractAdapter - Inherited

Class Method Summary

AbstractMysqlAdapter - Inherited

AbstractAdapter - Inherited

::ActiveSupport::DescendantsTracker - Inherited

Instance Attribute Summary

Mysql2::DatabaseStatements - Included

AbstractMysqlAdapter - Inherited

MySQL::SchemaStatements - Included

MySQL::DatabaseStatements - Included

AbstractAdapter - Inherited

DatabaseStatements - Included

SchemaStatements - Included

Instance Method Summary

Mysql2::DatabaseStatements - Included

AbstractMysqlAdapter - Inherited

MySQL::SchemaStatements - Included

MySQL::Quoting - Included

MySQL::DatabaseStatements - Included

AbstractAdapter - Inherited

Savepoints - Included

DatabaseLimits - Included

Quoting - Included

DatabaseStatements - Included

SchemaStatements - Included

::ActiveRecord::Migration::JoinTable - Included

::ActiveSupport::Callbacks - Included

Constructor Details

.new ⇒ Mysql2Adapter

Class Method Details

.initialize_type_map(m) (private)

.new_client(config)

Instance Attribute Details

#active? ⇒ Boolean (readonly)

#connected? ⇒ Boolean (readonly)

#savepoint_errors_invalidate_transactions? ⇒ Boolean (readonly)

#supports_comments? ⇒ Boolean (readonly)

#supports_comments_in_create? ⇒ Boolean (readonly)

#supports_json? ⇒ Boolean (readonly)

#supports_lazy_transactions? ⇒ Boolean (readonly)

#supports_savepoints? ⇒ Boolean (readonly)

Instance Method Details

#configure_connection (private)

#connect (private)

#default_prepared_statements (private)

#discard!

#disconnect!

#error_number(exception)

#full_version (private)

#get_full_version (private)

#reconnect (private)

#reset!

#text_type?(type) ⇒ Boolean (private)

#translate_exception(exception, message:, sql:, binds:) (private)

`::ActiveSupport::Callbacks` - Included

`DatabaseStatements` - Included

`AbstractAdapter` - Inherited

`MySQL::DatabaseStatements` - Included

`MySQL::Quoting` - Included

`MySQL::SchemaStatements` - Included

`AbstractMysqlAdapter` - Inherited

`AbstractMysqlAdapter` - Inherited

`AbstractAdapter` - Inherited

`AbstractMysqlAdapter` - Inherited

`AbstractAdapter` - Inherited

`::ActiveSupport::DescendantsTracker` - Inherited

`Mysql2::DatabaseStatements` - Included

`AbstractMysqlAdapter` - Inherited

`MySQL::SchemaStatements` - Included

`MySQL::DatabaseStatements` - Included

`AbstractAdapter` - Inherited

`DatabaseStatements` - Included

`SchemaStatements` - Included

`Mysql2::DatabaseStatements` - Included

`AbstractMysqlAdapter` - Inherited

`MySQL::SchemaStatements` - Included

`MySQL::Quoting` - Included

`MySQL::DatabaseStatements` - Included

`AbstractAdapter` - Inherited

`Savepoints` - Included

`DatabaseLimits` - Included

`Quoting` - Included

`DatabaseStatements` - Included

`SchemaStatements` - Included

`::ActiveRecord::Migration::JoinTable` - Included

`::ActiveSupport::Callbacks` - Included

.new ⇒ `Mysql2Adapter`

#active? ⇒ `Boolean` (readonly)

#connected? ⇒ `Boolean` (readonly)

#savepoint_errors_invalidate_transactions? ⇒ `Boolean` (readonly)

#supports_comments? ⇒ `Boolean` (readonly)

#supports_comments_in_create? ⇒ `Boolean` (readonly)

#supports_json? ⇒ `Boolean` (readonly)

#supports_lazy_transactions? ⇒ `Boolean` (readonly)

#supports_savepoints? ⇒ `Boolean` (readonly)

#text_type?(type) ⇒ `Boolean` (private)