Methods
Public Instance
- complex_expression_sql_append
- constant_sql_append
- count
- cross_apply
- disable_insert_output
- empty?
- escape_like
- full_text_search
- insert_select
- insert_select_sql
- into
- mssql_unicode_strings
- nolock
- outer_apply
- output
- quoted_identifier_append
- returning
- select_sql
- server_version
- supports_cte?
- supports_group_cube?
- supports_group_rollup?
- supports_grouping_sets?
- supports_insert_select?
- supports_intersect_except?
- supports_is_true?
- supports_join_using?
- supports_merge?
- supports_modifying_joins?
- supports_multiple_column_in?
- supports_nowait?
- supports_offsets_in_correlated_subqueries?
- supports_output_clause?
- supports_returning?
- supports_skip_locked?
- supports_where_true?
- supports_window_functions?
- with_mssql_unicode_strings
- with_ties
Protected Instance
Included modules
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 Instance methods
# File lib/sequel/adapters/shared/mssql.rb 588 def complex_expression_sql_append(sql, op, args) 589 case op 590 when :'||' 591 super(sql, :+, args) 592 when :LIKE, :"NOT LIKE" 593 super(sql, op, complex_expression_sql_like_args(args, " COLLATE Latin1_General_CS_AS)")) 594 when :ILIKE, :"NOT ILIKE" 595 super(sql, (op == :ILIKE ? :LIKE : :"NOT LIKE"), complex_expression_sql_like_args(args, " COLLATE Latin1_General_CI_AS)")) 596 when :<<, :>> 597 complex_expression_emulate_append(sql, op, args) 598 when :extract 599 part = args[0] 600 raise(Sequel::Error, "unsupported extract argument: #{part.inspect}") unless format = EXTRACT_MAP[part] 601 if part == :second 602 expr = args[1] 603 sql << "CAST((datepart(" << format.to_s << ', ' 604 literal_append(sql, expr) 605 sql << ') + datepart(ns, ' 606 literal_append(sql, expr) 607 sql << ")/1000000000.0) AS double precision)" 608 else 609 sql << "datepart(" << format.to_s << ', ' 610 literal_append(sql, args[1]) 611 sql << ')' 612 end 613 else 614 super 615 end 616 end
MSSQL
doesn’t support the SQL standard CURRENT_DATE or CURRENT_TIME
# File lib/sequel/adapters/shared/mssql.rb 619 def constant_sql_append(sql, constant) 620 if c = CONSTANT_MAP[constant] 621 sql << c 622 else 623 super 624 end 625 end
For a dataset with custom SQL, since it may include ORDER BY, you cannot wrap it in a subquery. Load entire query in this case to get the number of rows. In general, you should avoid calling this method on datasets with custom SQL.
# File lib/sequel/adapters/shared/mssql.rb 631 def count(*a, &block) 632 if (@opts[:sql] && a.empty? && !block) 633 naked.to_a.length 634 else 635 super 636 end 637 end
Uses CROSS APPLY to join the given table into the current dataset.
# File lib/sequel/adapters/shared/mssql.rb 640 def cross_apply(table) 641 join_table(:cross_apply, table) 642 end
Disable the use of INSERT OUTPUT
# File lib/sequel/adapters/shared/mssql.rb 645 def disable_insert_output 646 clone(:disable_insert_output=>true) 647 end
For a dataset with custom SQL, since it may include ORDER BY, you cannot wrap it in a subquery. Run query, and if it returns any records, return true. In general, you should avoid calling this method on datasets with custom SQL.
# File lib/sequel/adapters/shared/mssql.rb 653 def empty? 654 if @opts[:sql] 655 naked.each{return false} 656 true 657 else 658 super 659 end 660 end
MSSQL
treats [] as a metacharacter in LIKE expresions.
# File lib/sequel/adapters/shared/mssql.rb 663 def escape_like(string) 664 string.gsub(/[\\%_\[\]]/){|m| "\\#{m}"} 665 end
MSSQL
uses the CONTAINS keyword for full text search
# File lib/sequel/adapters/shared/mssql.rb 668 def full_text_search(cols, terms, opts = OPTS) 669 terms = "\"#{terms.join('" OR "')}\"" if terms.is_a?(Array) 670 where(Sequel.lit("CONTAINS (?, ?)", cols, terms)) 671 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 676 def insert_select(*values) 677 return unless supports_insert_select? 678 with_sql_first(insert_select_sql(*values)) || false 679 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 683 def insert_select_sql(*values) 684 ds = (opts[:output] || opts[:returning]) ? self : output(nil, [SQL::ColumnAll.new(:inserted)]) 685 ds.insert_sql(*values) 686 end
Specify a table for a SELECT … INTO query.
# File lib/sequel/adapters/shared/mssql.rb 689 def into(table) 690 clone(:into => table) 691 end
Use the database’s mssql_unicode_strings
setting if the dataset hasn’t overridden it.
# File lib/sequel/adapters/shared/mssql.rb 579 def mssql_unicode_strings 580 opts.has_key?(:mssql_unicode_strings) ? opts[:mssql_unicode_strings] : db.mssql_unicode_strings 581 end
Allows you to do a dirty read of uncommitted data using WITH (NOLOCK).
# File lib/sequel/adapters/shared/mssql.rb 694 def nolock 695 lock_style(:dirty) 696 end
Uses OUTER APPLY to join the given table into the current dataset.
# File lib/sequel/adapters/shared/mssql.rb 699 def outer_apply(table) 700 join_table(:outer_apply, table) 701 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 715 def output(into, values) 716 raise(Error, "SQL Server versions 2000 and earlier do not support the OUTPUT clause") unless supports_output_clause? 717 output = {} 718 case values 719 when Hash 720 output[:column_list], output[:select_list] = values.keys, values.values 721 when Array 722 output[:select_list] = values 723 end 724 output[:into] = into 725 clone(:output => output) 726 end
MSSQL
uses [] to quote identifiers.
# File lib/sequel/adapters/shared/mssql.rb 729 def quoted_identifier_append(sql, name) 730 sql << '[' << name.to_s.gsub(/\]/, ']]') << ']' 731 end
Emulate RETURNING using the output clause. This only handles values that are simple column references.
# File lib/sequel/adapters/shared/mssql.rb 734 def returning(*values) 735 values = values.map do |v| 736 unless r = unqualified_column_for(v) 737 raise(Error, "cannot emulate RETURNING via OUTPUT for value: #{v.inspect}") 738 end 739 r 740 end 741 clone(:returning=>values) 742 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 748 def select_sql 749 if @opts[:offset] 750 raise(Error, "Using with_ties is not supported with an offset on Microsoft SQL Server") if @opts[:limit_with_ties] 751 return order(1).select_sql if is_2012_or_later? && !@opts[:order] 752 end 753 super 754 end
The version of the database server.
# File lib/sequel/adapters/shared/mssql.rb 757 def server_version 758 db.server_version(@opts[:server]) 759 end
# File lib/sequel/adapters/shared/mssql.rb 761 def supports_cte?(type=:select) 762 is_2005_or_later? 763 end
MSSQL
2005+ supports GROUP BY CUBE.
# File lib/sequel/adapters/shared/mssql.rb 766 def supports_group_cube? 767 is_2005_or_later? 768 end
MSSQL
2005+ supports GROUP BY ROLLUP
# File lib/sequel/adapters/shared/mssql.rb 771 def supports_group_rollup? 772 is_2005_or_later? 773 end
MSSQL
2008+ supports GROUPING SETS
# File lib/sequel/adapters/shared/mssql.rb 776 def supports_grouping_sets? 777 is_2008_or_later? 778 end
MSSQL
supports insert_select
via the OUTPUT clause.
# File lib/sequel/adapters/shared/mssql.rb 781 def supports_insert_select? 782 supports_output_clause? && !opts[:disable_insert_output] 783 end
MSSQL
2005+ supports INTERSECT and EXCEPT
# File lib/sequel/adapters/shared/mssql.rb 786 def supports_intersect_except? 787 is_2005_or_later? 788 end
MSSQL
does not support IS TRUE
# File lib/sequel/adapters/shared/mssql.rb 791 def supports_is_true? 792 false 793 end
MSSQL
doesn’t support JOIN USING
# File lib/sequel/adapters/shared/mssql.rb 796 def supports_join_using? 797 false 798 end
MSSQL
2008+ supports MERGE
# File lib/sequel/adapters/shared/mssql.rb 801 def supports_merge? 802 is_2008_or_later? 803 end
MSSQL
2005+ supports modifying joined datasets
# File lib/sequel/adapters/shared/mssql.rb 806 def supports_modifying_joins? 807 is_2005_or_later? 808 end
MSSQL
does not support multiple columns for the IN/NOT IN operators
# File lib/sequel/adapters/shared/mssql.rb 811 def supports_multiple_column_in? 812 false 813 end
MSSQL
supports NOWAIT.
# File lib/sequel/adapters/shared/mssql.rb 816 def supports_nowait? 817 true 818 end
MSSQL
2005+ supports the OUTPUT clause.
# File lib/sequel/adapters/shared/mssql.rb 826 def supports_output_clause? 827 is_2005_or_later? 828 end
MSSQL
2005+ can emulate RETURNING via the OUTPUT clause.
# File lib/sequel/adapters/shared/mssql.rb 831 def supports_returning?(type) 832 supports_insert_select? 833 end
MSSQL
uses READPAST to skip locked rows.
# File lib/sequel/adapters/shared/mssql.rb 836 def supports_skip_locked? 837 true 838 end
MSSQL
cannot use WHERE 1.
# File lib/sequel/adapters/shared/mssql.rb 846 def supports_where_true? 847 false 848 end
MSSQL
2005+ supports window functions
# File lib/sequel/adapters/shared/mssql.rb 841 def supports_window_functions? 842 true 843 end
Return a cloned dataset with the mssql_unicode_strings
option set.
# File lib/sequel/adapters/shared/mssql.rb 584 def with_mssql_unicode_strings(v) 585 clone(:mssql_unicode_strings=>v) 586 end
Use WITH TIES when limiting the result set to also include additional rows matching the last row.
# File lib/sequel/adapters/shared/mssql.rb 852 def with_ties 853 clone(:limit_with_ties=>true) 854 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.
# File lib/sequel/adapters/shared/mssql.rb 862 def _import(columns, values, opts=OPTS) 863 if opts[:return] == :primary_key && !@opts[:output] 864 output(nil, [SQL::QualifiedIdentifier.new(:inserted, first_primary_key)])._import(columns, values, opts) 865 elsif @opts[:output] 866 # no transaction: our multi_insert_sql_strategy should guarantee 867 # that there's only ever a single statement. 868 sql = multi_insert_sql(columns, values)[0] 869 naked.with_sql(sql).map{|v| v.length == 1 ? v.values.first : v} 870 else 871 super 872 end 873 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 882 def compound_from_self 883 if @opts[:offset] && !@opts[:limit] && !is_2012_or_later? 884 clone(:limit=>LIMIT_ALL).from_self 885 elsif @opts[:order] && !(@opts[:sql] || @opts[:limit] || @opts[:offset]) 886 unordered 887 else 888 super 889 end 890 end