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class ActiveRecord::ConnectionAdapters::AbstractMysqlAdapter
Constants
- ER_CANNOT_ADD_FOREIGN
- ER_CANNOT_CREATE_TABLE
- ER_DATA_TOO_LONG
- ER_DO_NOT_HAVE_DEFAULT
- ER_DUP_ENTRY
-
See dev.mysql.com/doc/refman/5.7/en/error-messages-server.html
- ER_LOCK_DEADLOCK
- ER_LOCK_WAIT_TIMEOUT
- ER_NOT_NULL_VIOLATION
- ER_NO_REFERENCED_ROW_2
- ER_OUT_OF_RANGE
- ER_QUERY_INTERRUPTED
- ER_QUERY_TIMEOUT
- NATIVE_DATABASE_TYPES
Public Class Methods
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 29
class_attribute :emulate_booleans, default: true
By default, the Mysql2Adapter will consider all columns of type tinyint(1)
as boolean. If you wish to disable this emulation you can add the following line to your application.rb file:
ActiveRecord::ConnectionAdapters::Mysql2Adapter.emulate_booleans = false
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 53
def initialize(connection, logger, connection_options, config)
super(connection, logger, config)
@statements = StatementPool.new(self.class.type_cast_config_to_integer(config[:statement_limit]))
if version < "5.1.10"
raise "Your version of MySQL (#{version_string}) is too old. Active Record supports MySQL >= 5.1.10."
end
end
Public Instance Methods
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 199
def begin_db_transaction
execute "BEGIN"
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 203
def begin_isolated_db_transaction(isolation)
execute "SET TRANSACTION ISOLATION LEVEL #{transaction_isolation_levels.fetch(isolation)}"
begin_db_transaction
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 271
def charset
show_variable "character_set_database"
end
Returns the database character set.
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 165
def clear_cache!
reload_type_map
@statements.clear
end
Clears the prepared statements cache.
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 276
def collation
show_variable "collation_database"
end
Returns the database collation strategy.
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 250
def create_database(name, options = {})
if options[:collation]
execute "CREATE DATABASE #{quote_table_name(name)} DEFAULT COLLATE #{quote_table_name(options[:collation])}"
else
execute "CREATE DATABASE #{quote_table_name(name)} DEFAULT CHARACTER SET #{quote_table_name(options[:charset] || 'utf8')}"
end
end
Create a new MySQL database with optional :charset
and :collation
. Charset defaults to utf8.
Example:
create_database 'charset_test', charset: 'latin1', collation: 'latin1_bin'
create_database 'matt_development'
create_database 'matt_development', charset: :big5
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 266
def current_database
query_value("SELECT database()", "SCHEMA")
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 339
def drop_table(table_name, options = {})
execute "DROP#{' TEMPORARY' if options[:temporary]} TABLE#{' IF EXISTS' if options[:if_exists]} #{quote_table_name(table_name)}#{' CASCADE' if options[:force] == :cascade}"
end
Drops a table from the database.
:force
-
Set to
:cascade
to drop dependent objects as well. Defaults to false. :if_exists
-
Set to
true
to only drop the table if it exists. Defaults to false. :temporary
-
Set to
true
to drop temporary table. Defaults to false.
Although this command ignores most options
and the block if one is given, it can be helpful to provide these in a migration's change
method so it can be reverted. In that case, options
and the block will be used by create_table.
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 228
def empty_insert_statement_value
"VALUES ()"
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 184
def execute(sql, name = nil)
log(sql, name) do
ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
@connection.query(sql)
end
end
end
Executes the SQL statement in the context of this connection.
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 174
def explain(arel, binds = [])
sql = "EXPLAIN #{to_sql(arel, binds)}"
start = Time.now
result = exec_query(sql, "EXPLAIN", binds)
elapsed = Time.now - start
MySQL::ExplainPrettyPrinter.new.pp(result, elapsed)
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 390
def foreign_keys(table_name)
raise ArgumentError unless table_name.present?
scope = quoted_scope(table_name)
fk_info = exec_query(<<-SQL.strip_heredoc, "SCHEMA")
SELECT fk.referenced_table_name AS 'to_table',
fk.referenced_column_name AS 'primary_key',
fk.column_name AS 'column',
fk.constraint_name AS 'name',
rc.update_rule AS 'on_update',
rc.delete_rule AS 'on_delete'
FROM information_schema.referential_constraints rc
JOIN information_schema.key_column_usage fk
USING (constraint_schema, constraint_name)
WHERE fk.referenced_column_name IS NOT NULL
AND fk.table_schema = #{scope[:schema]}
AND fk.table_name = #{scope[:name]}
AND rc.constraint_schema = #{scope[:schema]}
AND rc.table_name = #{scope[:name]}
SQL
fk_info.map do |row|
options = {
column: row["column"],
name: row["name"],
primary_key: row["primary_key"]
}
options[:on_update] = extract_foreign_key_action(row["on_update"])
options[:on_delete] = extract_foreign_key_action(row["on_delete"])
ForeignKeyDefinition.new(table_name, row["to_table"], options)
end
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 131
def index_algorithms
{ default: "ALGORITHM = DEFAULT".dup, copy: "ALGORITHM = COPY".dup, inplace: "ALGORITHM = INPLACE".dup }
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 529
def insert_fixtures_set(fixture_set, tables_to_delete = [])
with_multi_statements do
super { discard_remaining_results }
end
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 127
def native_database_types
NATIVE_DATABASE_TYPES
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 236
def recreate_database(name, options = {})
drop_database(name)
sql = create_database(name, options)
reconnect!
sql
end
Drops the database specified on the name
attribute and creates it again using the provided options
.
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 343
def rename_index(table_name, old_name, new_name)
if supports_rename_index?
validate_index_length!(table_name, new_name)
execute "ALTER TABLE #{quote_table_name(table_name)} RENAME INDEX #{quote_table_name(old_name)} TO #{quote_table_name(new_name)}"
else
super
end
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 319
def rename_table(table_name, new_name)
execute "RENAME TABLE #{quote_table_name(table_name)} TO #{quote_table_name(new_name)}"
rename_table_indexes(table_name, new_name)
end
Renames a table.
Example:
rename_table('octopuses', 'octopi')
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 472
def show_variable(name)
query_value("SELECT @@#{name}", "SCHEMA")
rescue ActiveRecord::StatementInvalid
nil
end
SHOW VARIABLES LIKE 'name'
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 521
def strict_mode?
self.class.type_cast_config_to_boolean(@config.fetch(:strict, true))
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 115
def supports_advisory_locks?
true
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 99
def supports_datetime_with_precision?
if mariadb?
version >= "5.3.0"
else
version >= "5.6.4"
end
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 83
def supports_explain?
true
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 91
def supports_foreign_keys?
true
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 75
def supports_index_sort_order?
!mariadb? && version >= "8.0.1"
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 87
def supports_indexes_in_create?
true
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 79
def supports_transaction_isolation?
true
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 95
def supports_views?
true
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 107
def supports_virtual_columns?
if mariadb?
version >= "5.2.0"
else
version >= "5.7.5"
end
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 280
def truncate(table_name, name = nil)
execute "TRUNCATE TABLE #{quote_table_name(table_name)}", name
end
© 2004–2018 David Heinemeier Hansson
Licensed under the MIT License.