Class: ActiveRecord::ConnectionAdapters::MysqlAdapter

Inherits:
AbstractAdapter show all
Defined in:
lib/active_record/connection_adapters/mysql_adapter.rb

Overview

The MySQL adapter will work with both Ruby/MySQL, which is a Ruby-based MySQL adapter that comes bundled with Active Record, and with the faster C-based MySQL/Ruby adapter (available both as a gem and from www.tmtm.org/en/mysql/ruby/).

Options:

  • :host - Defaults to “localhost”.

  • :port - Defaults to 3306.

  • :socket - Defaults to “/tmp/mysql.sock”.

  • :username - Defaults to “root”

  • :password - Defaults to nothing.

  • :database - The name of the database. No default, must be provided.

  • :encoding - (Optional) Sets the client encoding by executing “SET NAMES <encoding>” after connection.

  • :reconnect - Defaults to false (See MySQL documentation: dev.mysql.com/doc/refman/5.0/en/auto-reconnect.html).

  • :sslca - Necessary to use MySQL with an SSL connection.

  • :sslkey - Necessary to use MySQL with an SSL connection.

  • :sslcert - Necessary to use MySQL with an SSL connection.

  • :sslcapath - Necessary to use MySQL with an SSL connection.

  • :sslcipher - Necessary to use MySQL with an SSL connection.

Constant Summary collapse

ADAPTER_NAME = 
'MySQL'.freeze
LOST_CONNECTION_ERROR_MESSAGES = 
[
"Server shutdown in progress",
"Broken pipe",
"Lost connection to MySQL server during query",
"MySQL server has gone away" ]
NATIVE_DATABASE_TYPES = 
{
  :primary_key => "int(11) DEFAULT NULL auto_increment PRIMARY KEY".freeze,
  :string      => { :name => "varchar", :limit => 255 },
  :text        => { :name => "text" },
  :integer     => { :name => "int", :limit => 4 },
  :float       => { :name => "float" },
  :decimal     => { :name => "decimal" },
  :datetime    => { :name => "datetime" },
  :timestamp   => { :name => "datetime" },
  :time        => { :name => "time" },
  :date        => { :name => "date" },
  :binary      => { :name => "blob" },
  :boolean     => { :name => "tinyint", :limit => 1 }
}

Instance Attribute Summary

Attributes included from QueryCache

#query_cache, #query_cache_enabled

Instance Method Summary collapse

Methods inherited from AbstractAdapter

#current_savepoint_name, #decrement_open_transactions, #increment_open_transactions, #log_info, #open_transactions, #prefetch_primary_key?, #raw_connection, #requires_reloading?, #reset_runtime, #supports_count_distinct?, #supports_ddl_transactions?, #transaction_joinable=, #verify!

Methods included from QueryCache

#cache, #clear_query_cache, #columns_with_query_cache, dirties_query_cache, included, #select_all_with_query_cache, #uncached

Methods included from DatabaseLimits

#column_name_length, #columns_per_multicolumn_index, #columns_per_table, #in_clause_length, #index_name_length, #indexes_per_table, #joins_per_query, #sql_query_length, #table_alias_length, #table_name_length

Methods included from Quoting

#quoted_date

Methods included from DatabaseStatements

#add_limit!, #add_lock!, #default_sequence_name, #delete, #empty_insert_statement, #insert, #insert_fixture, #outside_transaction?, #reset_sequence!, #select_all, #select_one, #select_value, #select_values, #transaction, #update

Methods included from SchemaStatements

#add_column_options!, #add_index, #add_order_by_for_association_limiting!, #add_timestamps, #assume_migrated_upto_version, #change_table, #distinct, #dump_schema_information, #index_exists?, #index_name, #initialize_schema_migrations_table, #remove_column, #remove_index, #remove_index!, #remove_timestamps, #rename_index, #table_alias_for, #table_exists?

Constructor Details

#initialize(connection, logger, connection_options, config) ⇒ MysqlAdapter

Returns a new instance of MysqlAdapter.



199
200
201
202
203
204
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 199

def initialize(connection, logger, connection_options, config)
  super(connection, logger)
  @connection_options, @config = connection_options, config
  @quoted_column_names, @quoted_table_names = {}, {}
  connect
end

Instance Method Details

#active? ⇒ Boolean

CONNECTION MANAGEMENT ====================================

Returns:

  • (Boolean) 


275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 275

def active?
  if @connection.respond_to?(:stat)
    @connection.stat
  else
    @connection.query 'select 1'
  end

  # mysql-ruby doesn't raise an exception when stat fails.
  if @connection.respond_to?(:errno)
    @connection.errno.zero?
  else
    true
  end
rescue Mysql::Error
  false
end

#adapter_name ⇒ Object

:nodoc:



206
207
208
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 206

def adapter_name #:nodoc:
  ADAPTER_NAME
end

#add_column(table_name, column_name, type, options = {}) ⇒ Object 



485
486
487
488
489
490
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 485

def add_column(table_name, column_name, type, options = {})
  add_column_sql = "ALTER TABLE #{quote_table_name(table_name)} ADD #{quote_column_name(column_name)} #{type_to_sql(type, options[:limit], options[:precision], options[:scale])}"
  add_column_options!(add_column_sql, options)
  add_column_position!(add_column_sql, options)
  execute(add_column_sql)
end

#add_column_position!(sql, options) ⇒ Object 



552
553
554
555
556
557
558
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 552

def add_column_position!(sql, options)
  if options[:first]
    sql << " FIRST"
  elsif options[:after]
    sql << " AFTER #{quote_column_name(options[:after])}"
  end
end

#add_limit_offset!(sql, options) ⇒ Object

:nodoc:



373
374
375
376
377
378
379
380
381
382
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 373

def add_limit_offset!(sql, options) #:nodoc:
  if limit = options[:limit]
    limit = sanitize_limit(limit)
    unless offset = options[:offset]
      sql << " LIMIT #{limit}"
    else
      sql << " LIMIT #{offset.to_i}, #{limit}"
    end
  end
end

#begin_db_transaction ⇒ Object

:nodoc:



343
344
345
346
347
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 343

def begin_db_transaction #:nodoc:
  execute "BEGIN"
rescue Exception
  # Transactions aren't supported
end

#case_sensitive_equality_operator ⇒ Object 



583
584
585
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 583

def case_sensitive_equality_operator
  "= BINARY"
end

#change_column(table_name, column_name, type, options = {}) ⇒ Object

:nodoc:



507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 507

def change_column(table_name, column_name, type, options = {}) #:nodoc:
  column = column_for(table_name, column_name)

  unless options_include_default?(options)
    options[:default] = column.default
  end

  unless options.has_key?(:null)
    options[:null] = column.null
  end

  change_column_sql = "ALTER TABLE #{quote_table_name(table_name)} CHANGE #{quote_column_name(column_name)} #{quote_column_name(column_name)} #{type_to_sql(type, options[:limit], options[:precision], options[:scale])}"
  add_column_options!(change_column_sql, options)
  add_column_position!(change_column_sql, options)
  execute(change_column_sql)
end

#change_column_default(table_name, column_name, default) ⇒ Object

:nodoc:



492
493
494
495
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 492

def change_column_default(table_name, column_name, default) #:nodoc:
  column = column_for(table_name, column_name)
  change_column table_name, column_name, column.sql_type, :default => default
end

#change_column_null(table_name, column_name, null, default = nil) ⇒ Object 



497
498
499
500
501
502
503
504
505
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 497

def change_column_null(table_name, column_name, null, default = nil)
  column = column_for(table_name, column_name)

  unless null || default.nil?
    execute("UPDATE #{quote_table_name(table_name)} SET #{quote_column_name(column_name)}=#{quote(default)} WHERE #{quote_column_name(column_name)} IS NULL")
  end

  change_column table_name, column_name, column.sql_type, :null => null
end

#charset ⇒ Object

Returns the database character set.



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

def charset
  show_variable 'character_set_database'
end

#collation ⇒ Object

Returns the database collation strategy.



434
435
436
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 434

def collation
  show_variable 'collation_database'
end

#columns(table_name, name = nil) ⇒ Object

:nodoc:



468
469
470
471
472
473
474
475
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 468

def columns(table_name, name = nil)#:nodoc:
  sql = "SHOW FIELDS FROM #{quote_table_name(table_name)}"
  columns = []
  result = execute(sql, name)
  result.each { |field| columns << MysqlColumn.new(field[0], field[4], field[1], field[2] == "YES") }
  result.free
  columns
end

#commit_db_transaction ⇒ Object

:nodoc:



349
350
351
352
353
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 349

def commit_db_transaction #:nodoc:
  execute "COMMIT"
rescue Exception
  # Transactions aren't supported
end

#create_database(name, options = {}) ⇒ Object

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



412
413
414
415
416
417
418
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 412

def create_database(name, options = {})
  if options[:collation]
    execute "CREATE DATABASE `#{name}` DEFAULT CHARACTER SET `#{options[:charset] || 'utf8'}` COLLATE `#{options[:collation]}`"
  else
    execute "CREATE DATABASE `#{name}` DEFAULT CHARACTER SET `#{options[:charset] || 'utf8'}`"
  end
end

#create_savepoint ⇒ Object 



361
362
363
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 361

def create_savepoint
  execute("SAVEPOINT #{current_savepoint_name}")
end

#create_table(table_name, options = {}) ⇒ Object

:nodoc:



477
478
479
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 477

def create_table(table_name, options = {}) #:nodoc:
  super(table_name, options.reverse_merge(:options => "ENGINE=InnoDB"))
end

#current_database ⇒ Object 



424
425
426
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 424

def current_database
  select_value 'SELECT DATABASE() as db'
end

#disable_referential_integrity(&block) ⇒ Object

REFERENTIAL INTEGRITY ====================================



262
263
264
265
266
267
268
269
270
271
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 262

def disable_referential_integrity(&block) #:nodoc:
  old = select_value("SELECT @@FOREIGN_KEY_CHECKS")

  begin
    update("SET FOREIGN_KEY_CHECKS = 0")
    yield
  ensure
    update("SET FOREIGN_KEY_CHECKS = #{old}")
  end
end

#disconnect! ⇒ Object 



297
298
299
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 297

def disconnect!
  @connection.close rescue nil
end

#drop_database(name) ⇒ Object

:nodoc:



420
421
422
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 420

def drop_database(name) #:nodoc:
  execute "DROP DATABASE IF EXISTS `#{name}`"
end

#drop_table(table_name, options = {}) ⇒ Object 



446
447
448
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 446

def drop_table(table_name, options = {})
  super(table_name, options)
end

#emulate_booleans ⇒ Object

:singleton-method: By default, the MysqlAdapter will consider all columns of type tinyint(1) as boolean. If you wish to disable this emulation (which was the default behavior in versions 0.13.1 and earlier) you can add the following line to your environment.rb file:

ActiveRecord::ConnectionAdapters::MysqlAdapter.emulate_booleans = false



171
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 171

cattr_accessor :emulate_booleans

#execute(sql, name = nil) ⇒ Object

Executes a SQL query and returns a MySQL::Result object. Note that you have to free the Result object after you’re done using it.



323
324
325
326
327
328
329
330
331
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 323

def execute(sql, name = nil) #:nodoc:
  log(sql, name) { @connection.query(sql) }
rescue ActiveRecord::StatementInvalid => exception
  if exception.message.split(":").first =~ /Packets out of order/
    raise ActiveRecord::StatementInvalid, "'Packets out of order' error was received from the database. Please update your mysql bindings (gem install mysql) and read http://dev.mysql.com/doc/mysql/en/password-hashing.html for more information.  If you're on Windows, use the Instant Rails installer to get the updated mysql bindings."
  else
    raise
  end
end

#indexes(table_name, name = nil) ⇒ Object

:nodoc:



450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 450

def indexes(table_name, name = nil)#:nodoc:
  indexes = []
  current_index = nil
  result = execute("SHOW KEYS FROM #{quote_table_name(table_name)}", name)
  result.each do |row|
    if current_index != row[2]
      next if row[2] == "PRIMARY" # skip the primary key
      current_index = row[2]
      indexes << IndexDefinition.new(row[0], row[2], row[1] == "0", [], [])
    end

    indexes.last.columns << row[4]
    indexes.last.lengths << row[7]
  end
  result.free
  indexes
end

#insert_sql(sql, name = nil, pk = nil, id_value = nil, sequence_name = nil) ⇒ Object

:nodoc:



333
334
335
336
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 333

def insert_sql(sql, name = nil, pk = nil, id_value = nil, sequence_name = nil) #:nodoc:
  super sql, name
  id_value || @connection.insert_id
end

#limited_update_conditions(where_sql, quoted_table_name, quoted_primary_key) ⇒ Object 



587
588
589
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 587

def limited_update_conditions(where_sql, quoted_table_name, quoted_primary_key)
  where_sql
end

#native_database_types ⇒ Object

:nodoc:



222
223
224
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 222

def native_database_types #:nodoc:
  NATIVE_DATABASE_TYPES
end

#pk_and_sequence_for(table) ⇒ Object

Returns a table’s primary key and belonging sequence.



567
568
569
570
571
572
573
574
575
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 567

def pk_and_sequence_for(table) #:nodoc:
  keys = []
  result = execute("describe #{quote_table_name(table)}")
  result.each_hash do |h|
    keys << h["Field"]if h["Key"] == "PRI"
  end
  result.free
  keys.length == 1 ? [keys.first, nil] : nil
end

#primary_key(table) ⇒ Object

Returns just a table’s primary key



578
579
580
581
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 578

def primary_key(table)
  pk_and_sequence = pk_and_sequence_for(table)
  pk_and_sequence && pk_and_sequence.first
end

#quote(value, column = nil) ⇒ Object

QUOTING ==================================================



229
230
231
232
233
234
235
236
237
238
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 229

def quote(value, column = nil)
  if value.kind_of?(String) && column && column.type == :binary && column.class.respond_to?(:string_to_binary)
    s = column.class.string_to_binary(value).unpack("H*")[0]
    "x'#{s}'"
  elsif value.kind_of?(BigDecimal)
    value.to_s("F")
  else
    super
  end
end

#quote_column_name(name) ⇒ Object

:nodoc:



240
241
242
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 240

def quote_column_name(name) #:nodoc:
  @quoted_column_names[name] ||= "`#{name.to_s.gsub('`', '``')}`"
end

#quote_string(string) ⇒ Object

:nodoc:



248
249
250
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 248

def quote_string(string) #:nodoc:
  @connection.quote(string)
end

#quote_table_name(name) ⇒ Object

:nodoc:



244
245
246
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 244

def quote_table_name(name) #:nodoc:
  @quoted_table_names[name] ||= quote_column_name(name).gsub('.', '`.`')
end

#quoted_false ⇒ Object 



256
257
258
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 256

def quoted_false
  QUOTED_FALSE
end

#quoted_true ⇒ Object 



252
253
254
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 252

def quoted_true
  QUOTED_TRUE
end

#reconnect! ⇒ Object 



292
293
294
295
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 292

def reconnect!
  disconnect!
  connect
end

#recreate_database(name, options = {}) ⇒ Object

:nodoc:



400
401
402
403
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 400

def recreate_database(name, options = {}) #:nodoc:
  drop_database(name)
  create_database(name, options)
end

#release_savepoint ⇒ Object 



369
370
371
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 369

def release_savepoint
  execute("RELEASE SAVEPOINT #{current_savepoint_name}")
end

#rename_column(table_name, column_name, new_column_name) ⇒ Object

:nodoc:



524
525
526
527
528
529
530
531
532
533
534
535
536
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 524

def rename_column(table_name, column_name, new_column_name) #:nodoc:
  options = {}
  if column = columns(table_name).find { |c| c.name == column_name.to_s }
    options[:default] = column.default
    options[:null] = column.null
  else
    raise ActiveRecordError, "No such column: #{table_name}.#{column_name}"
  end
  current_type = select_one("SHOW COLUMNS FROM #{quote_table_name(table_name)} LIKE '#{column_name}'")["Type"]
  rename_column_sql = "ALTER TABLE #{quote_table_name(table_name)} CHANGE #{quote_column_name(column_name)} #{quote_column_name(new_column_name)} #{current_type}"
  add_column_options!(rename_column_sql, options)
  execute(rename_column_sql)
end

#rename_table(table_name, new_name) ⇒ Object 



481
482
483
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 481

def rename_table(table_name, new_name)
  execute "RENAME TABLE #{quote_table_name(table_name)} TO #{quote_table_name(new_name)}"
end

#reset! ⇒ Object 



301
302
303
304
305
306
307
308
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 301

def reset!
  if @connection.respond_to?(:change_user)
    # See http://bugs.mysql.com/bug.php?id=33540 -- the workaround way to
    # reset the connection is to change the user to the same user.
    @connection.change_user(@config[:username], @config[:password], @config[:database])
    configure_connection
  end
end

#rollback_db_transaction ⇒ Object

:nodoc:



355
356
357
358
359
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 355

def rollback_db_transaction #:nodoc:
  execute "ROLLBACK"
rescue Exception
  # Transactions aren't supported
end

#rollback_to_savepoint ⇒ Object 



365
366
367
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 365

def rollback_to_savepoint
  execute("ROLLBACK TO SAVEPOINT #{current_savepoint_name}")
end

#select_rows(sql, name = nil) ⇒ Object

DATABASE STATEMENTS ======================================



312
313
314
315
316
317
318
319
320
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 312

def select_rows(sql, name = nil)
  @connection.query_with_result = true
  result = execute(sql, name)
  rows = []
  result.each { |row| rows << row }
  result.free
  @connection.more_results && @connection.next_result    # invoking stored procedures with CLIENT_MULTI_RESULTS requires this to tidy up else connection will be dropped
  rows
end

#show_variable(name) ⇒ Object

SHOW VARIABLES LIKE ‘name’



561
562
563
564
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 561

def show_variable(name)
  variables = select_all("SHOW VARIABLES LIKE '#{name}'")
  variables.first['Value'] unless variables.empty?
end

#structure_dump ⇒ Object

SCHEMA STATEMENTS ========================================



387
388
389
390
391
392
393
394
395
396
397
398
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 387

def structure_dump #:nodoc:
  if supports_views?
    sql = "SHOW FULL TABLES WHERE Table_type = 'BASE TABLE'"
  else
    sql = "SHOW TABLES"
  end

  select_all(sql).inject("") do |structure, table|
    table.delete('Table_type')
    structure += select_one("SHOW CREATE TABLE #{quote_table_name(table.to_a.first.last)}")["Create Table"] + ";\n\n"
  end
end

#supports_migrations? ⇒ Boolean

:nodoc:

Returns:

  • (Boolean) 


210
211
212
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 210

def supports_migrations? #:nodoc:
  true
end

#supports_primary_key? ⇒ Boolean

:nodoc:

Returns:

  • (Boolean) 


214
215
216
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 214

def supports_primary_key? #:nodoc:
  true
end

#supports_savepoints? ⇒ Boolean

:nodoc:

Returns:

  • (Boolean) 


218
219
220
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 218

def supports_savepoints? #:nodoc:
  true
end

#tables(name = nil) ⇒ Object

:nodoc:



438
439
440
441
442
443
444
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 438

def tables(name = nil) #:nodoc:
  tables = []
  result = execute("SHOW TABLES", name)
  result.each { |field| tables << field[0] }
  result.free
  tables
end

#type_to_sql(type, limit = nil, precision = nil, scale = nil) ⇒ Object

Maps logical Rails types to MySQL-specific data types.



539
540
541
542
543
544
545
546
547
548
549
550
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 539

def type_to_sql(type, limit = nil, precision = nil, scale = nil)
  return super unless type.to_s == 'integer'

  case limit
  when 1; 'tinyint'
  when 2; 'smallint'
  when 3; 'mediumint'
  when nil, 4, 11; 'int(11)'  # compatibility with MySQL default
  when 5..8; 'bigint'
  else raise(ActiveRecordError, "No integer type has byte size #{limit}")
  end
end

#update_sql(sql, name = nil) ⇒ Object

:nodoc:



338
339
340
341
 
# File 'lib/active_record/connection_adapters/mysql_adapter.rb', line 338

def update_sql(sql, name = nil) #:nodoc:
  super
  @connection.affected_rows
end