Module: Sequel::MySQL::DatasetMethods

Constants

 '1'.freeze
 '0'.freeze
 ', '.freeze
 ' LOCK IN SHARE MODE'.freeze
 Dataset.clause_methods(:delete, %w'from where order limit')
 Dataset.clause_methods(:insert, %w'ignore into columns values on_duplicate_key_update')
 Dataset.clause_methods(:select, %w'distinct columns from join where group having compounds order limit lock')
 Dataset.clause_methods(:update, %w'table set where order limit')

Public Instance methods

complex_expression_sql(op, args)

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

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 302
302:       def complex_expression_sql(op, args)
303:         case op
304:         when :~, '!~''!~', '~*''~*', '!~*''!~*', :LIKE, 'NOT LIKE''NOT LIKE', :ILIKE, 'NOT ILIKE''NOT ILIKE'
305:           "(#{literal(args.at(0))} #{'NOT ' if [:'NOT LIKE', :'NOT ILIKE', :'!~', :'!~*'].include?(op)}#{[:~, :'!~', :'~*', :'!~*'].include?(op) ? 'REGEXP' : 'LIKE'} #{'BINARY ' if [:~, :'!~', :LIKE, :'NOT LIKE'].include?(op)}#{literal(args.at(1))})"
306:         when '||''||'
307:           if args.length > 1
308:             "CONCAT(#{args.collect{|a| literal(a)}.join(', ')})"
309:           else
310:             literal(args.at(0))
311:           end
312:         when 'B~''B~'
313:           "CAST(~#{literal(args.at(0))} AS SIGNED INTEGER)"
314:         else
315:           super(op, args)
316:         end
317:       end

distinct(*args)

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

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 320
320:       def distinct(*args)
321:         args.empty? ? super : group(*args)
322:       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 325
325:       def for_share
326:         lock_style(:share)
327:       end

full_text_search(cols, terms, opts = {})

Adds full text filter

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 330
330:       def full_text_search(cols, terms, opts = {})
331:         filter(full_text_sql(cols, terms, opts))
332:       end

full_text_sql(cols, term, opts = {})

MySQL specific full text search syntax.

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 335
335:       def full_text_sql(cols, term, opts = {})
336:         "MATCH #{literal(Array(cols))} AGAINST (#{literal(Array(term).join(' '))}#{" IN BOOLEAN MODE" if opts[:boolean]})"
337:       end

having(*cond, &block)

MySQL allows HAVING clause on ungrouped datasets.

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 340
340:       def having(*cond, &block)
341:         _filter(:having, *cond, &block)
342:       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 370
370:       def insert_ignore
371:         clone(:insert_ignore=>true)
372:       end

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

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 346
346:       def join_table(type, table, expr=nil, table_alias={})
347:         type = :inner if (type == :cross) && !expr.nil?
348:         raise(Sequel::Error, "MySQL doesn't support FULL OUTER JOIN") if type == :full_outer
349:         super(type, table, expr, table_alias)
350:       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 354
354:       def join_type_sql(join_type)
355:         case join_type
356:         when :straight then 'STRAIGHT_JOIN'
357:         when :natural_inner then 'NATURAL LEFT JOIN'
358:         else super
359:         end
360:       end

multi_insert_sql(columns, values)

MySQL specific syntax for inserting multiple values at once.

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 398
398:       def multi_insert_sql(columns, values)
399:         [insert_sql(columns, LiteralString.new('VALUES ' + values.map {|r| literal(Array(r))}.join(COMMA_SEPARATOR)))]
400:       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 393
393:       def on_duplicate_key_update(*args)
394:         clone(:on_duplicate_key_update => args)
395:       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 404
404:       def provides_accurate_rows_matched?
405:         false
406:       end

quoted_identifier(c)

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

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 409
409:       def quoted_identifier(c)
410:         "`#{c}`"
411:       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 415
415:       def replace_sql(*values)
416:         clone(:replace=>true).insert_sql(*values)
417:       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 421
421:       def supports_distinct_on?
422:         true
423:       end

supports_intersect_except?()

MySQL does not support INTERSECT or EXCEPT

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 426
426:       def supports_intersect_except?
427:         false
428:       end

supports_modifying_joins?()

MySQL supports modifying joined datasets

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 431
431:       def supports_modifying_joins?
432:         true
433:       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 438
438:       def supports_timestamp_usecs?
439:         false
440:       end

Protected Instance methods

_insert_sql()

If this is an replace instead of an insert, use replace instead

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 445
445:       def _insert_sql
446:         @opts[:replace] ? clause_sql(:replace) : super
447:       end