| Module | Sequel::MSSQL |
| In: |
lib/sequel/extensions/mssql_emulate_lateral_with_apply.rb
lib/sequel/adapters/shared/mssql.rb |
| 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 |
# 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
# 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
Disable the use of INSERT OUTPUT
# File lib/sequel/adapters/shared/mssql.rb, line 564
564: def disable_insert_output
565: clone(:disable_insert_output=>true)
566: 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.
# 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.
# 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.
# 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.
# 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).
# File lib/sequel/adapters/shared/mssql.rb, line 600
600: def nolock
601: lock_style(:dirty)
602: 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])
# 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
Emulate RETURNING using the output clause. This only handles values that are simple column references.
# 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.
# 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.
# File lib/sequel/adapters/shared/mssql.rb, line 663
663: def server_version
664: db.server_version(@opts[:server])
665: end
# File lib/sequel/adapters/shared/mssql.rb, line 667
667: def supports_cte?(type=:select)
668: is_2005_or_later?
669: end
MSSQL supports insert_select via the OUTPUT clause.
# File lib/sequel/adapters/shared/mssql.rb, line 687
687: def supports_insert_select?
688: supports_output_clause? && !opts[:disable_insert_output]
689: end
Return a cloned dataset with the mssql_unicode_strings option set.
# File lib/sequel/adapters/shared/mssql.rb, line 515
515: def with_mssql_unicode_strings(v)
516: clone(:mssql_unicode_strings=>v)
517: end
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.
# 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
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.
# 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