Module: Sequel::MySQL::DatasetMethods

Constants

 '1'.freeze
 '0'.freeze
 ', '.freeze
 ' LOCK IN SHARE MODE'.freeze
 ' SQL_CALC_FOUND_ROWS'.freeze
 Dataset.clause_methods(:delete, %w'delete from where order limit')
 Dataset.clause_methods(:insert, %w'insert ignore into columns values on_duplicate_key_update')
 Dataset.clause_methods(:select, %w'select distinct calc_found_rows columns from join where group having compounds order limit lock')
 Dataset.clause_methods(:update, %w'update table set where order limit')
 Dataset::SPACE
 Dataset::PAREN_OPEN
 Dataset::PAREN_CLOSE
 Dataset::NOT_SPACE
 Dataset::FROM
 Dataset::INSERT
 Dataset::COMMA
 Dataset::LIMIT
 Dataset::GROUP_BY
 'REGEXP'.freeze
 'LIKE'.freeze
 'BINARY '.freeze
 "CONCAT".freeze
 "CAST(~".freeze
 " AS SIGNED INTEGER)".freeze
 'STRAIGHT_JOIN'.freeze
 'NATURAL LEFT JOIN'.freeze
 '`'.freeze
 " ()".freeze
 " VALUES ()".freeze
 " IGNORE".freeze
 'REPLACE'.freeze
 " ON DUPLICATE KEY UPDATE ".freeze
 '=VALUES('.freeze
 '='.freeze
 ' WITH ROLLUP'.freeze

Public Instance methods

calc_found_rows()

Sets up the select methods to use SQL_CALC_FOUND_ROWS option.

  dataset.calc_found_rows.limit(10)
  # SELECT SQL_CALC_FOUND_ROWS * FROM table LIMIT 10

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 413
413:       def calc_found_rows
414:         clone(:calc_found_rows => true)
415:       end

complex_expression_sql_append(sql, op, args)

MySQL specific syntax for LIKE/REGEXP searches, as well as string concatenation.

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 369
369:       def complex_expression_sql_append(sql, op, args)
370:         case op
371:         when :IN, "NOT IN""NOT IN"
372:           ds = args.at(1)
373:           if ds.is_a?(Sequel::Dataset) && ds.opts[:limit]
374:             super(sql, op, [args.at(0), ds.from_self])
375:           else
376:             super
377:           end
378:         when :~, '!~''!~', '~*''~*', '!~*''!~*', :LIKE, 'NOT LIKE''NOT LIKE', :ILIKE, 'NOT ILIKE''NOT ILIKE'
379:           sql << PAREN_OPEN
380:           literal_append(sql, args.at(0))
381:           sql << SPACE
382:           sql << 'NOT ' if ['NOT LIKE''NOT LIKE', 'NOT ILIKE''NOT ILIKE', '!~''!~', '!~*''!~*'].include?(op)
383:           sql << ([:~, '!~''!~', '~*''~*', '!~*''!~*'].include?(op) ? REGEXP : LIKE)
384:           sql << SPACE
385:           sql << BINARY if [:~, '!~''!~', :LIKE, 'NOT LIKE''NOT LIKE'].include?(op)
386:           literal_append(sql, args.at(1))
387:           sql << PAREN_CLOSE
388:         when '||''||'
389:           if args.length > 1
390:             sql << CONCAT
391:             array_sql_append(sql, args)
392:           else
393:             literal_append(sql, args.at(0))
394:           end
395:         when 'B~''B~'
396:           sql << CAST_BITCOMP_OPEN
397:           literal_append(sql, args.at(0))
398:           sql << CAST_BITCOMP_CLOSE
399:         else
400:           super
401:         end
402:       end

distinct(*args)

Use GROUP BY instead of DISTINCT ON if arguments are provided.

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 405
405:       def distinct(*args)
406:         args.empty? ? super : group(*args)
407:       end

for_share()

Return a cloned dataset which will use LOCK IN SHARE MODE to lock returned rows.

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 418
418:       def for_share
419:         lock_style(:share)
420:       end

full_text_search(cols, terms, opts = {})

Adds full text filter

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 423
423:       def full_text_search(cols, terms, opts = {})
424:         filter(full_text_sql(cols, terms, opts))
425:       end

full_text_sql(cols, terms, opts = {})

MySQL specific full text search syntax.

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 428
428:       def full_text_sql(cols, terms, opts = {})
429:         terms = terms.join(' ') if terms.is_a?(Array)
430:         SQL::PlaceholderLiteralString.new("MATCH ? AGAINST (?#{" IN BOOLEAN MODE" if opts[:boolean]})", [Array(cols), terms], true)
431:       end

having(*cond, &block)

MySQL allows HAVING clause on ungrouped datasets.

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 434
434:       def having(*cond, &block)
435:         _filter(:having, *cond, &block)
436:       end

insert_ignore()

Sets up the insert methods to use INSERT IGNORE. Useful if you have a unique key and want to just skip inserting rows that violate the unique key restriction.

  dataset.insert_ignore.multi_insert(
   [{:name => 'a', :value => 1}, {:name => 'b', :value => 2}]
  )
  # INSERT IGNORE INTO tablename (name, value) VALUES (a, 1), (b, 2)

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 467
467:       def insert_ignore
468:         clone(:insert_ignore=>true)
469:       end

join_table(type, table, expr=nil, table_alias={}, &block)

Transforms an CROSS JOIN to an INNER JOIN if the expr is not nil. Raises an error on use of :full_outer type, since MySQL doesn‘t support it.

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 440
440:       def join_table(type, table, expr=nil, table_alias={}, &block)
441:         type = :inner if (type == :cross) && !expr.nil?
442:         raise(Sequel::Error, "MySQL doesn't support FULL OUTER JOIN") if type == :full_outer
443:         super(type, table, expr, table_alias, &block)
444:       end

join_type_sql(join_type)

Transforms :natural_inner to NATURAL LEFT JOIN and straight to STRAIGHT_JOIN.

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 448
448:       def join_type_sql(join_type)
449:         case join_type
450:         when :straight
451:           STRAIGHT_JOIN
452:         when :natural_inner
453:           NATURAL_LEFT_JOIN
454:         else
455:           super
456:         end
457:       end

multi_insert_sql(columns, values)

MySQL specific syntax for inserting multiple values at once.

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 495
495:       def multi_insert_sql(columns, values)
496:         sql = LiteralString.new('VALUES ')
497:         expression_list_append(sql, values.map{|r| Array(r)})
498:         [insert_sql(columns, sql)]
499:       end

on_duplicate_key_update(*args)

Sets up the insert methods to use ON DUPLICATE KEY UPDATE If you pass no arguments, ALL fields will be updated with the new values. If you pass the fields you want then ONLY those field will be updated.

Useful if you have a unique key and want to update inserting rows that violate the unique key restriction.

  dataset.on_duplicate_key_update.multi_insert(
   [{:name => 'a', :value => 1}, {:name => 'b', :value => 2}]
  )
  # INSERT INTO tablename (name, value) VALUES (a, 1), (b, 2)
  # ON DUPLICATE KEY UPDATE name=VALUES(name), value=VALUES(value)

  dataset.on_duplicate_key_update(:value).multi_insert(
    [{:name => 'a', :value => 1}, {:name => 'b', :value => 2}]
  )
  # INSERT INTO tablename (name, value) VALUES (a, 1), (b, 2)
  # ON DUPLICATE KEY UPDATE value=VALUES(value)

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 490
490:       def on_duplicate_key_update(*args)
491:         clone(:on_duplicate_key_update => args)
492:       end

provides_accurate_rows_matched?()

MySQL uses the number of rows actually modified in the update, instead of the number of matched by the filter.

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 503
503:       def provides_accurate_rows_matched?
504:         false
505:       end

quoted_identifier_append(sql, c)

MySQL uses the nonstandard ` (backtick) for quoting identifiers.

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 508
508:       def quoted_identifier_append(sql, c)
509:         sql << BACKTICK << c.to_s << BACKTICK
510:       end

replace_sql(*values)

MySQL specific syntax for REPLACE (aka UPSERT, or update if exists, insert if it doesn‘t).

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 514
514:       def replace_sql(*values)
515:         clone(:replace=>true).insert_sql(*values)
516:       end

supports_distinct_on?()

MySQL can emulate DISTINCT ON with its non-standard GROUP BY implementation, though the rows returned cannot be made deterministic through ordering.

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 520
520:       def supports_distinct_on?
521:         true
522:       end

supports_group_rollup?()

MySQL supports GROUP BY WITH ROLLUP (but not CUBE)

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 525
525:       def supports_group_rollup?
526:         true
527:       end

supports_intersect_except?()

MySQL does not support INTERSECT or EXCEPT

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 530
530:       def supports_intersect_except?
531:         false
532:       end

supports_modifying_joins?()

MySQL supports modifying joined datasets

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 535
535:       def supports_modifying_joins?
536:         true
537:       end

supports_ordered_distinct_on?()

MySQL‘s DISTINCT ON emulation using GROUP BY does not respect the queries ORDER BY clause.

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 541
541:       def supports_ordered_distinct_on?
542:         false
543:       end

supports_timestamp_usecs?()

MySQL does support fractional timestamps in literal timestamps, but it ignores them. Also, using them seems to cause problems on 1.9. Since they are ignored anyway, not using them is probably best.

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 548
548:       def supports_timestamp_usecs?
549:         false
550:       end