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 ignore table set where order limit')
 Dataset::APOS
 Dataset::APOS_RE
 Dataset::DOUBLE_APOS
 Dataset::SPACE
 Dataset::PAREN_OPEN
 Dataset::PAREN_CLOSE
 Dataset::NOT_SPACE
 Dataset::FROM
 Dataset::INSERT
 Dataset::COMMA
 Dataset::LIMIT
 Dataset::GROUP_BY
 Dataset::ESCAPE
 Dataset::BACKSLASH
 'REGEXP'.freeze
 'LIKE'.freeze
 'BINARY '.freeze
 "CONCAT".freeze
 "CAST(~".freeze
 " AS SIGNED INTEGER)".freeze
 'STRAIGHT_JOIN'.freeze
 'NATURAL LEFT JOIN'.freeze
 '`'.freeze
 /`/.freeze
 '``'.freeze
 " ()".freeze
 " VALUES ()".freeze
 " IGNORE".freeze
 'REPLACE'.freeze
 " ON DUPLICATE KEY UPDATE ".freeze
 '=VALUES('.freeze
 '='.freeze
 ' WITH ROLLUP'.freeze
 ["(MATCH ".freeze, " AGAINST (".freeze, "))".freeze].freeze
 ["(MATCH ".freeze, " AGAINST (".freeze, " IN BOOLEAN MODE))".freeze].freeze
 'EXPLAIN '.freeze
 'EXPLAIN EXTENDED '.freeze
 /\\/.freeze
 "\\\\\\\\".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 617
617:       def calc_found_rows
618:         clone(:calc_found_rows => true)
619:       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 569
569:       def complex_expression_sql_append(sql, op, args)
570:         case op
571:         when :IN, "NOT IN""NOT IN"
572:           ds = args.at(1)
573:           if ds.is_a?(Sequel::Dataset) && ds.opts[:limit]
574:             super(sql, op, [args.at(0), ds.from_self])
575:           else
576:             super
577:           end
578:         when :~, '!~''!~', '~*''~*', '!~*''!~*', :LIKE, 'NOT LIKE''NOT LIKE', :ILIKE, 'NOT ILIKE''NOT ILIKE'
579:           sql << PAREN_OPEN
580:           literal_append(sql, args.at(0))
581:           sql << SPACE
582:           sql << 'NOT ' if ['NOT LIKE''NOT LIKE', 'NOT ILIKE''NOT ILIKE', '!~''!~', '!~*''!~*'].include?(op)
583:           sql << ([:~, '!~''!~', '~*''~*', '!~*''!~*'].include?(op) ? REGEXP : LIKE)
584:           sql << SPACE
585:           sql << BINARY if [:~, '!~''!~', :LIKE, 'NOT LIKE''NOT LIKE'].include?(op)
586:           literal_append(sql, args.at(1))
587:           if [:LIKE, 'NOT LIKE''NOT LIKE', :ILIKE, 'NOT ILIKE''NOT ILIKE'].include?(op)
588:             sql << ESCAPE
589:             literal_append(sql, BACKSLASH)
590:           end
591:           sql << PAREN_CLOSE
592:         when '||''||'
593:           if args.length > 1
594:             sql << CONCAT
595:             array_sql_append(sql, args)
596:           else
597:             literal_append(sql, args.at(0))
598:           end
599:         when 'B~''B~'
600:           sql << CAST_BITCOMP_OPEN
601:           literal_append(sql, args.at(0))
602:           sql << CAST_BITCOMP_CLOSE
603:         else
604:           super
605:         end
606:       end

distinct(*args)

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

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 609
609:       def distinct(*args)
610:         args.empty? ? super : group(*args)
611:       end

explain(opts={})

Return the results of an EXPLAIN query as a string. Options:

:extended :

Use EXPLAIN EXPTENDED instead of EXPLAIN if true.

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 623
623:       def explain(opts={})
624:         # Load the PrettyTable class, needed for explain output
625:         Sequel.extension(:_pretty_table) unless defined?(Sequel::PrettyTable)
626: 
627:         ds = db.send(:metadata_dataset).with_sql((opts[:extended] ? EXPLAIN_EXTENDED : EXPLAIN) + select_sql).naked
628:         rows = ds.all
629:         Sequel::PrettyTable.string(rows, ds.columns)
630:       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 633
633:       def for_share
634:         lock_style(:share)
635:       end

full_text_search(cols, terms, opts = {})

Adds full text filter

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 638
638:       def full_text_search(cols, terms, opts = {})
639:         filter(full_text_sql(cols, terms, opts))
640:       end

full_text_sql(cols, terms, opts = {})

MySQL specific full text search syntax.

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 643
643:       def full_text_sql(cols, terms, opts = {})
644:         terms = terms.join(' ') if terms.is_a?(Array)
645:         SQL::PlaceholderLiteralString.new((opts[:boolean] ? MATCH_AGAINST_BOOLEAN : MATCH_AGAINST), [Array(cols), terms])
646:       end

having(*cond, &block)

MySQL allows HAVING clause on ungrouped datasets.

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 649
649:       def having(*cond, &block)
650:         _filter(:having, *cond, &block)
651:       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 682
682:       def insert_ignore
683:         clone(:insert_ignore=>true)
684:       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 655
655:       def join_table(type, table, expr=nil, table_alias={}, &block)
656:         type = :inner if (type == :cross) && !expr.nil?
657:         raise(Sequel::Error, "MySQL doesn't support FULL OUTER JOIN") if type == :full_outer
658:         super(type, table, expr, table_alias, &block)
659:       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 663
663:       def join_type_sql(join_type)
664:         case join_type
665:         when :straight
666:           STRAIGHT_JOIN
667:         when :natural_inner
668:           NATURAL_LEFT_JOIN
669:         else
670:           super
671:         end
672:       end

multi_insert_sql(columns, values)

MySQL specific syntax for inserting multiple values at once.

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 710
710:       def multi_insert_sql(columns, values)
711:         sql = LiteralString.new('VALUES ')
712:         expression_list_append(sql, values.map{|r| Array(r)})
713:         [insert_sql(columns, sql)]
714:       end

multi_replace(*values)

Replace multiple rows in a single query.

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 733
733:       def multi_replace(*values)
734:         clone(:replace=>true).multi_insert(*values)
735:       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 705
705:       def on_duplicate_key_update(*args)
706:         clone(:on_duplicate_key_update => args)
707:       end

quoted_identifier_append(sql, c)

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

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 717
717:       def quoted_identifier_append(sql, c)
718:         sql << BACKTICK << c.to_s.gsub(BACKTICK_RE, DOUBLE_BACKTICK) << BACKTICK
719:       end

replace(*values)

Execute a REPLACE statement on the database.

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 722
722:       def replace(*values)
723:         execute_insert(replace_sql(*values))
724:       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 728
728:       def replace_sql(*values)
729:         clone(:replace=>true).insert_sql(*values)
730:       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 739
739:       def supports_distinct_on?
740:         true
741:       end

supports_group_rollup?()

MySQL supports GROUP BY WITH ROLLUP (but not CUBE)

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 744
744:       def supports_group_rollup?
745:         true
746:       end

supports_intersect_except?()

MySQL does not support INTERSECT or EXCEPT

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 749
749:       def supports_intersect_except?
750:         false
751:       end

supports_modifying_joins?()

MySQL supports modifying joined datasets

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 754
754:       def supports_modifying_joins?
755:         true
756:       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 760
760:       def supports_ordered_distinct_on?
761:         false
762:       end

supports_regexp?()

MySQL supports pattern matching via regular expressions

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 765
765:       def supports_regexp?
766:         true
767:       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 772
772:       def supports_timestamp_usecs?
773:         false
774:       end

update_ignore()

Sets up the update methods to use UPDATE IGNORE. Useful if you have a unique key and want to just skip updating rows that violate the unique key restriction.

  dataset.update_ignore.update({:name => 'a', :value => 1})
  # UPDATE IGNORE tablename SET name = 'a', value = 1

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 782
782:       def update_ignore
783:         clone(:update_ignore=>true)
784:       end