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class ActiveRecord::ConnectionAdapters::AbstractMysqlAdapter
Constants
- ER_CANNOT_ADD_FOREIGN
- ER_CANNOT_CREATE_TABLE
- ER_DATA_TOO_LONG
- ER_DB_CREATE_EXISTS
-
See dev.mysql.com/doc/mysql-errors/en/server-error-reference.html
- ER_DO_NOT_HAVE_DEFAULT
- ER_DUP_ENTRY
- ER_FILSORT_ABORT
- ER_FK_INCOMPATIBLE_COLUMNS
- ER_LOCK_DEADLOCK
- ER_LOCK_WAIT_TIMEOUT
- ER_NOT_NULL_VIOLATION
- ER_NO_REFERENCED_ROW
- ER_NO_REFERENCED_ROW_2
- ER_OUT_OF_RANGE
- ER_QUERY_INTERRUPTED
- ER_QUERY_TIMEOUT
- ER_ROW_IS_REFERENCED
- ER_ROW_IS_REFERENCED_2
- NATIVE_DATABASE_TYPES
- TYPE_MAP
- TYPE_MAP_WITH_BOOLEAN
Public Class Methods
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 27
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 54
def initialize(connection, logger, connection_options, config)
super(connection, logger, config)
end
ActiveRecord::ConnectionAdapters::QueryCache::new
Public Instance Methods
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 274
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 418
def check_constraints(table_name)
if supports_check_constraints?
scope = quoted_scope(table_name)
sql = <<~SQL
SELECT cc.constraint_name AS 'name',
cc.check_clause AS 'expression'
FROM information_schema.check_constraints cc
JOIN information_schema.table_constraints tc
USING (constraint_schema, constraint_name)
WHERE tc.table_schema = #{scope[:schema]}
AND tc.table_name = #{scope[:name]}
AND cc.constraint_schema = #{scope[:schema]}
SQL
sql += " AND cc.table_name = #{scope[:name]}" if mariadb?
chk_info = exec_query(sql, "SCHEMA")
chk_info.map do |row|
options = {
name: row["name"]
}
expression = row["expression"]
expression = expression[1..-2] unless mariadb? # remove parentheses added by mysql
CheckConstraintDefinition.new(table_name, expression, options)
end
else
raise NotImplementedError
end
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 279
def collation
show_variable "collation_database"
end
Returns the database collation strategy.
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 249
def create_database(name, options = {})
if options[:collation]
execute "CREATE DATABASE #{quote_table_name(name)} DEFAULT COLLATE #{quote_table_name(options[:collation])}"
elsif options[:charset]
execute "CREATE DATABASE #{quote_table_name(name)} DEFAULT CHARACTER SET #{quote_table_name(options[:charset])}"
elsif row_format_dynamic_by_default?
execute "CREATE DATABASE #{quote_table_name(name)} DEFAULT CHARACTER SET `utf8mb4`"
else
raise "Configure a supported :charset and ensure innodb_large_prefix is enabled to support indexes on varchar(255) string columns."
end
end
Create a new MySQL
database with optional :charset
and :collation
. Charset defaults to utf8mb4.
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 269
def current_database
query_value("SELECT database()", "SCHEMA")
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 326
def drop_table(table_name, **options)
schema_cache.clear_data_source_cache!(table_name.to_s)
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 199
def execute(sql, name = nil, async: false)
raw_execute(sql, name, async: async)
end
Executes the SQL statement in the context of this connection.
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 382
def foreign_keys(table_name)
raise ArgumentError unless table_name.present?
scope = quoted_scope(table_name)
fk_info = exec_query(<<~SQL, "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 158
def index_algorithms
{
default: "ALGORITHM = DEFAULT",
copy: "ALGORITHM = COPY",
inplace: "ALGORITHM = INPLACE",
instant: "ALGORITHM = INSTANT",
}
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 154
def native_database_types
NATIVE_DATABASE_TYPES
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 235
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 331
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 304
def rename_table(table_name, new_name)
schema_cache.clear_data_source_cache!(table_name.to_s)
schema_cache.clear_data_source_cache!(new_name.to_s)
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 479
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 530
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 129
def supports_advisory_locks?
true
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 68
def supports_bulk_alter?
true
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 96
def supports_check_constraints?
if mariadb?
database_version >= "10.2.1"
else
database_version >= "8.0.16"
end
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 121
def supports_common_table_expressions?
if mariadb?
database_version >= "10.2.1"
else
database_version >= "8.0.1"
end
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 108
def supports_datetime_with_precision?
mariadb? || database_version >= "5.6.4"
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 84
def supports_explain?
true
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 76
def supports_expression_index?
!mariadb? && database_version >= "8.0.13"
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 92
def supports_foreign_keys?
true
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 72
def supports_index_sort_order?
!mariadb? && database_version >= "8.0.1"
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 88
def supports_indexes_in_create?
true
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 133
def supports_insert_on_duplicate_skip?
true
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 137
def supports_insert_on_duplicate_update?
true
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 117
def supports_optimizer_hints?
!mariadb? && database_version >= "5.7.7"
end
See dev.mysql.com/doc/refman/en/optimizer-hints.html for more details.
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 80
def supports_transaction_isolation?
true
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 104
def supports_views?
true
end
# File activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 112
def supports_virtual_columns?
mariadb? || database_version >= "5.7.5"
end
© 2004–2021 David Heinemeier Hansson
Licensed under the MIT License.