module Sequel::MSSQL
Constants
- CONSTANT_MAP
- EXTRACT_MAP
- LIMIT_ALL
Public Class Methods
# File lib/sequel/adapters/shared/mssql.rb, line 9 def self.mock_adapter_setup(db) db.instance_exec do @server_version = 11000000 end end
Public Instance Methods
# File lib/sequel/adapters/shared/mssql.rb, line 518 def complex_expression_sql_append(sql, op, args) case op when :'||' super(sql, :+, args) when :LIKE, :"NOT LIKE" super(sql, op, args.map{|a| Sequel.lit(["(", " COLLATE Latin1_General_CS_AS)"], a)}) when :ILIKE, :"NOT ILIKE" super(sql, (op == :ILIKE ? :LIKE : :"NOT LIKE"), args.map{|a| Sequel.lit(["(", " COLLATE Latin1_General_CI_AS)"], a)}) when :<<, :>> complex_expression_emulate_append(sql, op, args) when :extract part = args[0] raise(Sequel::Error, "unsupported extract argument: #{part.inspect}") unless format = EXTRACT_MAP[part] if part == :second expr = args[1] sql << "CAST((datepart(" << format.to_s << ', ' literal_append(sql, expr) sql << ') + datepart(ns, ' literal_append(sql, expr) sql << ")/1000000000.0) AS double precision)" else sql << "datepart(" << format.to_s << ', ' literal_append(sql, args[1]) sql << ')' end else super end end
Uses CROSS APPLY to join the given table into the current dataset.
# File lib/sequel/adapters/shared/mssql.rb, line 558 def cross_apply(table) join_table(:cross_apply, table) end
Disable the use of INSERT OUTPUT
# File lib/sequel/adapters/shared/mssql.rb, line 563 def disable_insert_output clone(:disable_insert_output=>true) end
MSSQL treats [] as a metacharacter in LIKE expresions.
# File lib/sequel/adapters/shared/mssql.rb, line 568 def escape_like(string) string.gsub(/[\%_\[\]]/){|m| "\\#{m}"} end
MSSQL uses the CONTAINS keyword for full text search
# File lib/sequel/adapters/shared/mssql.rb, line 573 def full_text_search(cols, terms, opts = OPTS) terms = "\"#{terms.join('" OR "')}\"" if terms.is_a?(Array) where(Sequel.lit("CONTAINS (?, ?)", cols, terms)) 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 581 def insert_select(*values) return unless supports_insert_select? with_sql_first(insert_select_sql(*values)) || false 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 588 def insert_select_sql(*values) ds = (opts[:output] || opts[:returning]) ? self : output(nil, [SQL::ColumnAll.new(:inserted)]) ds.insert_sql(*values) end
Specify a table for a SELECT … INTO query.
# File lib/sequel/adapters/shared/mssql.rb, line 594 def into(table) clone(:into => table) end
Use the database's #mssql_unicode_strings setting if the dataset hasn't overridden it.
# File lib/sequel/adapters/shared/mssql.rb, line 509 def mssql_unicode_strings opts.has_key?(:mssql_unicode_strings) ? opts[:mssql_unicode_strings] : db.mssql_unicode_strings end
Allows you to do a dirty read of uncommitted data using WITH (NOLOCK).
# File lib/sequel/adapters/shared/mssql.rb, line 599 def nolock lock_style(:dirty) end
Uses OUTER APPLY to join the given table into the current dataset.
# File lib/sequel/adapters/shared/mssql.rb, line 604 def outer_apply(table) join_table(:outer_apply, table) 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 620 def output(into, values) raise(Error, "SQL Server versions 2000 and earlier do not support the OUTPUT clause") unless supports_output_clause? output = {} case values when Hash output[:column_list], output[:select_list] = values.keys, values.values when Array output[:select_list] = values end output[:into] = into clone(:output => output) end
MSSQL uses [] to quote identifiers.
# File lib/sequel/adapters/shared/mssql.rb, line 634 def quoted_identifier_append(sql, name) sql << '[' << name.to_s.gsub(/\]/, ']]') << ']' end
Emulate RETURNING using the output clause. This only handles values that are simple column references.
# File lib/sequel/adapters/shared/mssql.rb, line 639 def returning(*values) values = values.map do |v| unless r = unqualified_column_for(v) raise(Error, "cannot emulate RETURNING via OUTPUT for value: #{v.inspect}") end r end clone(:returning=>values) 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 653 def select_sql if @opts[:offset] && !@opts[:order] && is_2012_or_later? order(1).select_sql else super end end
The version of the database server.
# File lib/sequel/adapters/shared/mssql.rb, line 662 def server_version db.server_version(@opts[:server]) end
# File lib/sequel/adapters/shared/mssql.rb, line 666 def supports_cte?(type=:select) is_2005_or_later? end
MSSQL 2005+ supports GROUP BY CUBE.
# File lib/sequel/adapters/shared/mssql.rb, line 671 def supports_group_cube? is_2005_or_later? end
MSSQL 2005+ supports GROUP BY ROLLUP
# File lib/sequel/adapters/shared/mssql.rb, line 676 def supports_group_rollup? is_2005_or_later? end
MSSQL 2008+ supports GROUPING SETS
# File lib/sequel/adapters/shared/mssql.rb, line 681 def supports_grouping_sets? is_2008_or_later? end
MSSQL supports #insert_select via the OUTPUT clause.
# File lib/sequel/adapters/shared/mssql.rb, line 686 def supports_insert_select? supports_output_clause? && !opts[:disable_insert_output] end
MSSQL 2005+ supports INTERSECT and EXCEPT
# File lib/sequel/adapters/shared/mssql.rb, line 691 def supports_intersect_except? is_2005_or_later? end
MSSQL does not support IS TRUE
# File lib/sequel/adapters/shared/mssql.rb, line 696 def supports_is_true? false end
MSSQL doesn't support JOIN USING
# File lib/sequel/adapters/shared/mssql.rb, line 701 def supports_join_using? false end
MSSQL 2005+ supports modifying joined datasets
# File lib/sequel/adapters/shared/mssql.rb, line 706 def supports_modifying_joins? is_2005_or_later? end
MSSQL does not support multiple columns for the IN/NOT IN operators
# File lib/sequel/adapters/shared/mssql.rb, line 711 def supports_multiple_column_in? false end
MSSQL supports NOWAIT.
# File lib/sequel/adapters/shared/mssql.rb, line 716 def supports_nowait? true end
MSSQL 2005+ supports the OUTPUT clause.
# File lib/sequel/adapters/shared/mssql.rb, line 726 def supports_output_clause? is_2005_or_later? end
MSSQL 2005+ can emulate RETURNING via the OUTPUT clause.
# File lib/sequel/adapters/shared/mssql.rb, line 731 def supports_returning?(type) supports_insert_select? end
MSSQL uses READPAST to skip locked rows.
# File lib/sequel/adapters/shared/mssql.rb, line 736 def supports_skip_locked? true end
MSSQL cannot use WHERE 1.
# File lib/sequel/adapters/shared/mssql.rb, line 746 def supports_where_true? false end
MSSQL 2005+ supports window functions
# File lib/sequel/adapters/shared/mssql.rb, line 741 def supports_window_functions? true end
Return a cloned dataset with the #mssql_unicode_strings option set.
# File lib/sequel/adapters/shared/mssql.rb, line 514 def with_mssql_unicode_strings(v) clone(:mssql_unicode_strings=>v) 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, line 756 def _import(columns, values, opts=OPTS) if opts[:return] == :primary_key && !@opts[:output] output(nil, [SQL::QualifiedIdentifier.new(:inserted, first_primary_key)])._import(columns, values, opts) elsif @opts[:output] statements = multi_insert_sql(columns, values) @db.transaction(opts.merge(:server=>@opts[:server])) do statements.map{|st| with_sql(st)} end.first.map{|v| v.length == 1 ? v.values.first : v} else super end end
MSSQL does not allow ordering in sub-clauses unless TOP (limit) is specified
# File lib/sequel/adapters/shared/mssql.rb, line 770 def aggregate_dataset (options_overlap(Sequel::Dataset::COUNT_FROM_SELF_OPTS) && !options_overlap([:limit])) ? unordered.from_self : super 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 781 def compound_from_self if @opts[:offset] && !@opts[:limit] && !is_2012_or_later? clone(:limit=>LIMIT_ALL).from_self elsif @opts[:order] && !(@opts[:sql] || @opts[:limit] || @opts[:offset]) unordered else super end end
Private Instance Methods
Allow update and delete for unordered, limited datasets only.
# File lib/sequel/adapters/shared/mssql.rb, line 794 def check_not_limited!(type) return if @opts[:skip_limit_check] && type != :truncate raise Sequel::InvalidOperation, "Dataset##{type} not suppored on ordered, limited datasets" if opts[:order] && opts[:limit] super if type == :truncate || @opts[:offset] end
Use strict ISO-8601 format with T between date and time, since that is the format that is multilanguage and not DATEFORMAT dependent.
# File lib/sequel/adapters/shared/mssql.rb, line 818 def default_timestamp_format "'%Y-%m-%dT%H:%M:%S%N%z'" end
MSSQL supports FROM clauses in DELETE and UPDATE statements.
# File lib/sequel/adapters/shared/mssql.rb, line 829 def delete_from2_sql(sql) if joined_dataset? select_from_sql(sql) select_join_sql(sql) end end
Only include the primary table in the main delete clause
# File lib/sequel/adapters/shared/mssql.rb, line 823 def delete_from_sql(sql) sql << ' FROM ' source_list_append(sql, @opts[:from][0..0]) end
# File lib/sequel/adapters/shared/mssql.rb, line 837 def delete_output_sql(sql) output_sql(sql, :DELETED) end
There is no function on Microsoft SQL Server that does character length and respects trailing spaces (datalength respects trailing spaces, but counts bytes instead of characters). Use a hack to work around the trailing spaces issue.
# File lib/sequel/adapters/shared/mssql.rb, line 845 def emulate_function?(name) name == :char_length || name == :trim end
# File lib/sequel/adapters/shared/mssql.rb, line 849 def emulate_function_sql_append(sql, f) case f.name when :char_length literal_append(sql, SQL::Function.new(:len, Sequel.join([f.args.first, 'x'])) - 1) when :trim literal_append(sql, SQL::Function.new(:ltrim, SQL::Function.new(:rtrim, f.args.first))) end end
Microsoft SQL Server 2012+ has native support for offsets, but only for ordered datasets.
# File lib/sequel/adapters/shared/mssql.rb, line 859 def emulate_offset_with_row_number? super && !(is_2012_or_later? && @opts[:order]) end
Return the first primary key for the current table. If this table has multiple primary keys, this will only return one of them. Used by #_import.
# File lib/sequel/adapters/shared/mssql.rb, line 865 def first_primary_key @db.schema(self).map{|k, v| k if v[:primary_key] == true}.compact.first end
# File lib/sequel/adapters/shared/mssql.rb, line 869 def insert_output_sql(sql) output_sql(sql, :INSERTED) end
Whether we are using SQL Server 2005 or later.
# File lib/sequel/adapters/shared/mssql.rb, line 801 def is_2005_or_later? server_version >= 9000000 end
Whether we are using SQL Server 2008 or later.
# File lib/sequel/adapters/shared/mssql.rb, line 806 def is_2008_or_later? server_version >= 10000000 end
Whether we are using SQL Server 2012 or later.
# File lib/sequel/adapters/shared/mssql.rb, line 811 def is_2012_or_later? server_version >= 11000000 end
Handle CROSS APPLY and OUTER APPLY JOIN types
# File lib/sequel/adapters/shared/mssql.rb, line 875 def join_type_sql(join_type) case join_type when :cross_apply 'CROSS APPLY' when :outer_apply 'OUTER APPLY' else super end end
MSSQL uses a literal hexidecimal number for blob strings
# File lib/sequel/adapters/shared/mssql.rb, line 887 def literal_blob_append(sql, v) sql << '0x' << v.unpack("H*").first end
Use YYYYmmdd format, since that's the only format that is multilanguage and not DATEFORMAT dependent.
# File lib/sequel/adapters/shared/mssql.rb, line 893 def literal_date(v) v.strftime("'%Y%m%d'") end
Use 0 for false on MSSQL
# File lib/sequel/adapters/shared/mssql.rb, line 898 def literal_false '0' end
Optionally use unicode string syntax for all strings. Don't double backslashes.
# File lib/sequel/adapters/shared/mssql.rb, line 904 def literal_string_append(sql, v) sql << (mssql_unicode_strings ? "N'" : "'") sql << v.gsub("'", "''").gsub(/\((?:\r\n)|\n)/, '\\\\\1\1') << "'" end
Use 1 for true on MSSQL
# File lib/sequel/adapters/shared/mssql.rb, line 910 def literal_true '1' end
MSSQL 2008+ supports multiple rows in the VALUES clause, older versions can use UNION.
# File lib/sequel/adapters/shared/mssql.rb, line 916 def multi_insert_sql_strategy is_2008_or_later? ? :values : :union end
# File lib/sequel/adapters/shared/mssql.rb, line 920 def non_sql_option?(key) super || key == :disable_insert_output || key == :mssql_unicode_strings end
# File lib/sequel/adapters/shared/mssql.rb, line 1017 def output_list_sql(sql, output) sql << " OUTPUT " column_list_append(sql, output[:select_list]) if into = output[:into] sql << " INTO " identifier_append(sql, into) if column_list = output[:column_list] sql << ' (' source_list_append(sql, column_list) sql << ')' end end end
# File lib/sequel/adapters/shared/mssql.rb, line 1031 def output_returning_sql(sql, type, values) sql << " OUTPUT " if values.empty? literal_append(sql, SQL::ColumnAll.new(type)) else values = values.map do |v| case v when SQL::AliasedExpression Sequel.qualify(type, v.expression).as(v.alias) else Sequel.qualify(type, v) end end column_list_append(sql, values) end end
# File lib/sequel/adapters/shared/mssql.rb, line 1008 def output_sql(sql, type) return unless supports_output_clause? if output = @opts[:output] output_list_sql(sql, output) elsif values = @opts[:returning] output_returning_sql(sql, type, values) end end
# File lib/sequel/adapters/shared/mssql.rb, line 924 def select_into_sql(sql) if i = @opts[:into] sql << " INTO " identifier_append(sql, i) end end
MSSQL 2000 uses TOP N for limit. For MSSQL 2005+ TOP (N) is used to allow the limit to be a bound variable.
# File lib/sequel/adapters/shared/mssql.rb, line 933 def select_limit_sql(sql) if l = @opts[:limit] return if is_2012_or_later? && @opts[:order] && @opts[:offset] shared_limit_sql(sql, l) end end
Handle dirty, skip locked, and for update locking
# File lib/sequel/adapters/shared/mssql.rb, line 963 def select_lock_sql(sql) lock = @opts[:lock] skip_locked = @opts[:skip_locked] nowait = @opts[:nowait] for_update = lock == :update dirty = lock == :dirty lock_hint = for_update || dirty if lock_hint || skip_locked sql << " WITH (" if lock_hint sql << (for_update ? 'UPDLOCK' : 'NOLOCK') end if skip_locked || nowait sql << ', ' if lock_hint sql << (skip_locked ? "READPAST" : "NOWAIT") end sql << ')' else super end end
On 2012+ when there is an order with an offset, append the offset (and possible limit) at the end of the order clause.
# File lib/sequel/adapters/shared/mssql.rb, line 991 def select_order_sql(sql) super if is_2012_or_later? && @opts[:order] if o = @opts[:offset] sql << " OFFSET " literal_append(sql, o) sql << " ROWS" if l = @opts[:limit] sql << " FETCH NEXT " literal_append(sql, l) sql << " ROWS ONLY" end end end end
MSSQL supports 100-nsec precision for time columns, but ruby by default only supports usec precision.
# File lib/sequel/adapters/shared/mssql.rb, line 1050 def sqltime_precision 6 end
# File lib/sequel/adapters/shared/mssql.rb, line 955 def update_limit_sql(sql) if l = @opts[:limit] shared_limit_sql(sql, l) end end
Only include the primary table in the main update clause
# File lib/sequel/adapters/shared/mssql.rb, line 1062 def update_table_sql(sql) sql << ' ' source_list_append(sql, @opts[:from][0..0]) end
# File lib/sequel/adapters/shared/mssql.rb, line 1067 def uses_with_rollup? !is_2008_or_later? end