Module Sequel::MSSQL
In: lib/sequel/extensions/mssql_emulate_lateral_with_apply.rb
lib/sequel/adapters/shared/mssql.rb

Methods

Included Modules

EmulateOffsetWithRowNumber

Classes and Modules

Module Sequel::MSSQL::DatabaseMethods
Module Sequel::MSSQL::DatasetMethods
Module Sequel::MSSQL::EmulateLateralWithApply

Constants

CONSTANT_MAP = {:CURRENT_DATE=>'CAST(CURRENT_TIMESTAMP AS DATE)'.freeze, :CURRENT_TIME=>'CAST(CURRENT_TIMESTAMP AS TIME)'.freeze}.freeze
EXTRACT_MAP = {:year=>"yy", :month=>"m", :day=>"d", :hour=>"hh", :minute=>"n", :second=>"s"}.freeze
LIMIT_ALL = Object.new.freeze

Public Class methods

[Source]

    # File lib/sequel/adapters/shared/mssql.rb, line 10
10:     def self.mock_adapter_setup(db)
11:       db.instance_exec do
12:         @server_version = 11000000
13:       end
14:     end

Public Instance methods

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 519
519:       def complex_expression_sql_append(sql, op, args)
520:         case op
521:         when '||''||'
522:           super(sql, :+, args)
523:         when :LIKE, "NOT LIKE""NOT LIKE"
524:           super(sql, op, args.map{|a| Sequel.lit(["(", " COLLATE Latin1_General_CS_AS)"], a)})
525:         when :ILIKE, "NOT ILIKE""NOT ILIKE"
526:           super(sql, (op == :ILIKE ? :LIKE : "NOT LIKE""NOT LIKE"), args.map{|a| Sequel.lit(["(", " COLLATE Latin1_General_CI_AS)"], a)})
527:         when :<<, :>>
528:           complex_expression_emulate_append(sql, op, args)
529:         when :extract
530:           part = args[0]
531:           raise(Sequel::Error, "unsupported extract argument: #{part.inspect}") unless format = EXTRACT_MAP[part]
532:           if part == :second
533:             expr = args[1]
534:             sql << "CAST((datepart(" << format.to_s << ', '
535:             literal_append(sql, expr)
536:             sql << ') + datepart(ns, '
537:             literal_append(sql, expr)
538:             sql << ")/1000000000.0) AS double precision)"
539:           else
540:             sql << "datepart(" << format.to_s << ', '
541:             literal_append(sql, args[1])
542:             sql << ')'
543:           end
544:         else
545:           super
546:         end
547:       end

MSSQL doesn‘t support the SQL standard CURRENT_DATE or CURRENT_TIME

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 550
550:       def constant_sql_append(sql, constant)
551:         if c = CONSTANT_MAP[constant]
552:           sql << c
553:         else
554:           super
555:         end
556:       end

Uses CROSS APPLY to join the given table into the current dataset.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 559
559:       def cross_apply(table)
560:         join_table(:cross_apply, table)
561:       end

Disable the use of INSERT OUTPUT

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 564
564:       def disable_insert_output
565:         clone(:disable_insert_output=>true)
566:       end

MSSQL treats [] as a metacharacter in LIKE expresions.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 569
569:       def escape_like(string)
570:         string.gsub(/[\\%_\[\]]/){|m| "\\#{m}"}
571:       end

MSSQL uses the CONTAINS keyword for full text search

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 574
574:       def full_text_search(cols, terms, opts = OPTS)
575:         terms = "\"#{terms.join('" OR "')}\"" if terms.is_a?(Array)
576:         where(Sequel.lit("CONTAINS (?, ?)", cols, terms))
577:       end

Insert a record, returning the record inserted, using OUTPUT. Always returns nil without running an INSERT statement if disable_insert_output is used. If the query runs but returns no values, returns false.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 582
582:       def insert_select(*values)
583:         return unless supports_insert_select?
584:         with_sql_first(insert_select_sql(*values)) || false
585:       end

Add OUTPUT clause unless there is already an existing output clause, then return the SQL to insert.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 589
589:       def insert_select_sql(*values)
590:         ds = (opts[:output] || opts[:returning]) ? self : output(nil, [SQL::ColumnAll.new(:inserted)])
591:         ds.insert_sql(*values)
592:       end

Specify a table for a SELECT … INTO query.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 595
595:       def into(table)
596:         clone(:into => table)
597:       end

Use the database‘s mssql_unicode_strings setting if the dataset hasn‘t overridden it.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 510
510:       def mssql_unicode_strings
511:         opts.has_key?(:mssql_unicode_strings) ? opts[:mssql_unicode_strings] : db.mssql_unicode_strings
512:       end

Allows you to do a dirty read of uncommitted data using WITH (NOLOCK).

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 600
600:       def nolock
601:         lock_style(:dirty)
602:       end

Uses OUTER APPLY to join the given table into the current dataset.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 605
605:       def outer_apply(table)
606:         join_table(:outer_apply, table)
607:       end

Include an OUTPUT clause in the eventual INSERT, UPDATE, or DELETE query.

The first argument is the table to output into, and the second argument is either an Array of column values to select, or a Hash which maps output column names to selected values, in the style of insert or update.

Output into a returned result set is not currently supported.

Examples:

  dataset.output(:output_table, [Sequel[:deleted][:id], Sequel[:deleted][:name]])
  dataset.output(:output_table, id: Sequel[:inserted][:id], name: Sequel[:inserted][:name])

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 621
621:       def output(into, values)
622:         raise(Error, "SQL Server versions 2000 and earlier do not support the OUTPUT clause") unless supports_output_clause?
623:         output = {}
624:         case values
625:         when Hash
626:           output[:column_list], output[:select_list] = values.keys, values.values
627:         when Array
628:           output[:select_list] = values
629:         end
630:         output[:into] = into
631:         clone(:output => output)
632:       end

MSSQL uses [] to quote identifiers.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 635
635:       def quoted_identifier_append(sql, name)
636:         sql << '[' << name.to_s.gsub(/\]/, ']]') << ']'
637:       end

Emulate RETURNING using the output clause. This only handles values that are simple column references.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 640
640:       def returning(*values)
641:         values = values.map do |v|
642:           unless r = unqualified_column_for(v)
643:             raise(Error, "cannot emulate RETURNING via OUTPUT for value: #{v.inspect}")
644:           end
645:           r
646:         end
647:         clone(:returning=>values)
648:       end

On MSSQL 2012+ add a default order to the current dataset if an offset is used. The default offset emulation using a subquery would be used in the unordered case by default, and that also adds a default order, so it‘s better to just avoid the subquery.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 654
654:       def select_sql
655:         if @opts[:offset] && !@opts[:order] && is_2012_or_later?
656:           order(1).select_sql
657:         else
658:           super
659:         end
660:       end

The version of the database server.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 663
663:       def server_version
664:         db.server_version(@opts[:server])
665:       end

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 667
667:       def supports_cte?(type=:select)
668:         is_2005_or_later?
669:       end

MSSQL 2005+ supports GROUP BY CUBE.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 672
672:       def supports_group_cube?
673:         is_2005_or_later?
674:       end

MSSQL 2005+ supports GROUP BY ROLLUP

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 677
677:       def supports_group_rollup?
678:         is_2005_or_later?
679:       end

MSSQL 2008+ supports GROUPING SETS

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 682
682:       def supports_grouping_sets?
683:         is_2008_or_later?
684:       end

MSSQL supports insert_select via the OUTPUT clause.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 687
687:       def supports_insert_select?
688:         supports_output_clause? && !opts[:disable_insert_output]
689:       end

MSSQL 2005+ supports INTERSECT and EXCEPT

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 692
692:       def supports_intersect_except?
693:         is_2005_or_later?
694:       end

MSSQL does not support IS TRUE

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 697
697:       def supports_is_true?
698:         false
699:       end

MSSQL doesn‘t support JOIN USING

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 702
702:       def supports_join_using?
703:         false
704:       end

MSSQL 2005+ supports modifying joined datasets

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 707
707:       def supports_modifying_joins?
708:         is_2005_or_later?
709:       end

MSSQL does not support multiple columns for the IN/NOT IN operators

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 712
712:       def supports_multiple_column_in?
713:         false
714:       end

MSSQL supports NOWAIT.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 717
717:       def supports_nowait?
718:         true
719:       end

MSSQL 2012+ supports offsets in correlated subqueries.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 722
722:       def supports_offsets_in_correlated_subqueries?
723:         is_2012_or_later?
724:       end

MSSQL 2005+ supports the OUTPUT clause.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 727
727:       def supports_output_clause?
728:         is_2005_or_later?
729:       end

MSSQL 2005+ can emulate RETURNING via the OUTPUT clause.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 732
732:       def supports_returning?(type)
733:         supports_insert_select?
734:       end

MSSQL uses READPAST to skip locked rows.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 737
737:       def supports_skip_locked?
738:         true
739:       end

MSSQL cannot use WHERE 1.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 747
747:       def supports_where_true?
748:         false
749:       end

MSSQL 2005+ supports window functions

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 742
742:       def supports_window_functions?
743:         true
744:       end

Return a cloned dataset with the mssql_unicode_strings option set.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 515
515:       def with_mssql_unicode_strings(v)
516:         clone(:mssql_unicode_strings=>v)
517:       end

Protected Instance methods

If returned primary keys are requested, use OUTPUT unless already set on the dataset. If OUTPUT is already set, use existing returning values. If OUTPUT is only set to return a single columns, return an array of just that column. Otherwise, return an array of hashes.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 757
757:       def _import(columns, values, opts=OPTS)
758:         if opts[:return] == :primary_key && !@opts[:output]
759:           output(nil, [SQL::QualifiedIdentifier.new(:inserted, first_primary_key)])._import(columns, values, opts)
760:         elsif @opts[:output]
761:           statements = multi_insert_sql(columns, values)
762:           @db.transaction(opts.merge(:server=>@opts[:server])) do
763:             statements.map{|st| with_sql(st)}
764:           end.first.map{|v| v.length == 1 ? v.values.first : v}
765:         else
766:           super
767:         end
768:       end

MSSQL does not allow ordering in sub-clauses unless TOP (limit) is specified

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 771
771:       def aggregate_dataset
772:         (options_overlap(Sequel::Dataset::COUNT_FROM_SELF_OPTS) && !options_overlap([:limit])) ? unordered.from_self : super
773:       end

If the dataset using a order without a limit or offset or custom SQL, remove the order. Compounds on Microsoft SQL Server have undefined order unless the result is specifically ordered. Applying the current order before the compound doesn‘t work in all cases, such as when qualified identifiers are used. If you want to ensure a order for a compound dataset, apply the order after all compounds have been added.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 782
782:       def compound_from_self
783:         if @opts[:offset] && !@opts[:limit] && !is_2012_or_later?
784:           clone(:limit=>LIMIT_ALL).from_self
785:         elsif @opts[:order]  && !(@opts[:sql] || @opts[:limit] || @opts[:offset])
786:           unordered
787:         else
788:           super
789:         end
790:       end

[Validate]