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

MSSQL doesn‘t support the SQL standard CURRENT_DATE or CURRENT_TIME

[Source]

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

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

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 563
563:       def cross_apply(table)
564:         join_table(:cross_apply, table)
565:       end

Disable the use of INSERT OUTPUT

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 568
568:       def disable_insert_output
569:         clone(:disable_insert_output=>true)
570:       end

MSSQL treats [] as a metacharacter in LIKE expresions.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 573
573:       def escape_like(string)
574:         string.gsub(/[\\%_\[\]]/){|m| "\\#{m}"}
575:       end

MSSQL uses the CONTAINS keyword for full text search

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 578
578:       def full_text_search(cols, terms, opts = OPTS)
579:         terms = "\"#{terms.join('" OR "')}\"" if terms.is_a?(Array)
580:         where(Sequel.lit("CONTAINS (?, ?)", cols, terms))
581:       end

Use the OUTPUT clause to get the value of all columns for the newly inserted record.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 584
584:       def insert_select(*values)
585:         return unless supports_insert_select?
586:         with_sql_first(insert_select_sql(*values))
587:       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 591
591:       def insert_select_sql(*values)
592:         ds = (opts[:output] || opts[:returning]) ? self : output(nil, [SQL::ColumnAll.new(:inserted)])
593:         ds.insert_sql(*values)
594:       end

Specify a table for a SELECT … INTO query.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 597
597:       def into(table)
598:         clone(:into => table)
599:       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 514
514:       def mssql_unicode_strings
515:         opts.has_key?(:mssql_unicode_strings) ? opts[:mssql_unicode_strings] : db.mssql_unicode_strings
516:       end

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

[Source]

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

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

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 607
607:       def outer_apply(table)
608:         join_table(:outer_apply, table)
609:       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 623
623:       def output(into, values)
624:         raise(Error, "SQL Server versions 2000 and earlier do not support the OUTPUT clause") unless supports_output_clause?
625:         output = {}
626:         case values
627:         when Hash
628:           output[:column_list], output[:select_list] = values.keys, values.values
629:         when Array
630:           output[:select_list] = values
631:         end
632:         output[:into] = into
633:         clone(:output => output)
634:       end

MSSQL uses [] to quote identifiers.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 637
637:       def quoted_identifier_append(sql, name)
638:         sql << '[' << name.to_s.gsub(/\]/, ']]') << ']'
639:       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 642
642:       def returning(*values)
643:         values = values.map do |v|
644:           unless r = unqualified_column_for(v)
645:             raise(Error, "cannot emulate RETURNING via OUTPUT for value: #{v.inspect}")
646:           end
647:           r
648:         end
649:         clone(:returning=>values)
650:       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 656
656:       def select_sql
657:         if @opts[:offset] && !@opts[:order] && is_2012_or_later?
658:           order(1).select_sql
659:         else
660:           super
661:         end
662:       end

The version of the database server.

[Source]

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

[Source]

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

MSSQL 2005+ supports GROUP BY CUBE.

[Source]

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

MSSQL 2005+ supports GROUP BY ROLLUP

[Source]

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

MSSQL 2008+ supports GROUPING SETS

[Source]

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

MSSQL supports insert_select via the OUTPUT clause.

[Source]

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

MSSQL 2005+ supports INTERSECT and EXCEPT

[Source]

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

MSSQL does not support IS TRUE

[Source]

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

MSSQL doesn‘t support JOIN USING

[Source]

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

MSSQL 2005+ supports modifying joined datasets

[Source]

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

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

[Source]

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

MSSQL 2012+ supports offsets in correlated subqueries.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 719
719:       def supports_offsets_in_correlated_subqueries?
720:         is_2012_or_later?
721:       end

MSSQL 2005+ supports the OUTPUT clause.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 724
724:       def supports_output_clause?
725:         is_2005_or_later?
726:       end

MSSQL 2005+ can emulate RETURNING via the OUTPUT clause.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 729
729:       def supports_returning?(type)
730:         supports_insert_select?
731:       end

MSSQL uses READPAST to skip locked rows.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 734
734:       def supports_skip_locked?
735:         true
736:       end

MSSQL cannot use WHERE 1.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 744
744:       def supports_where_true?
745:         false
746:       end

MSSQL 2005+ supports window functions

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 739
739:       def supports_window_functions?
740:         true
741:       end

Return a cloned dataset with the mssql_unicode_strings option set.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 519
519:       def with_mssql_unicode_strings(v)
520:         clone(:mssql_unicode_strings=>v)
521:       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 754
754:       def _import(columns, values, opts=OPTS)
755:         if opts[:return] == :primary_key && !@opts[:output]
756:           output(nil, [SQL::QualifiedIdentifier.new(:inserted, first_primary_key)])._import(columns, values, opts)
757:         elsif @opts[:output]
758:           statements = multi_insert_sql(columns, values)
759:           @db.transaction(opts.merge(:server=>@opts[:server])) do
760:             statements.map{|st| with_sql(st)}
761:           end.first.map{|v| v.length == 1 ? v.values.first : v}
762:         else
763:           super
764:         end
765:       end

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

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 768
768:       def aggregate_dataset
769:         (options_overlap(Sequel::Dataset::COUNT_FROM_SELF_OPTS) && !options_overlap([:limit])) ? unordered.from_self : super
770:       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 779
779:       def compound_from_self
780:         if @opts[:offset] && !@opts[:limit] && !is_2012_or_later?
781:           clone(:limit=>LIMIT_ALL).from_self
782:         elsif @opts[:order]  && !(@opts[:sql] || @opts[:limit] || @opts[:offset])
783:           unordered
784:         else
785:           super
786:         end
787:       end

[Validate]