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

Methods

Constants

BOOL_TRUE = '1'.freeze
BOOL_FALSE = '0'.freeze
COMMA_SEPARATOR = ', '.freeze
DELETE_CLAUSE_METHODS = Dataset.clause_methods(:delete, %w'with from output from2 where')
INSERT_CLAUSE_METHODS = Dataset.clause_methods(:insert, %w'with into columns output values')
SELECT_CLAUSE_METHODS = Dataset.clause_methods(:select, %w'with distinct limit columns into from lock join where group having order compounds')
UPDATE_CLAUSE_METHODS = Dataset.clause_methods(:update, %w'with table set output from where')
NOLOCK = ' WITH (NOLOCK)'.freeze
UPDLOCK = ' WITH (UPDLOCK)'.freeze
WILDCARD = LiteralString.new('*').freeze
CONSTANT_MAP = {:CURRENT_DATE=>'CAST(CURRENT_TIMESTAMP AS DATE)'.freeze, :CURRENT_TIME=>'CAST(CURRENT_TIMESTAMP AS TIME)'.freeze}

Public Instance methods

MSSQL uses + for string concatenation, and LIKE is case insensitive by default.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 210
210:       def complex_expression_sql(op, args)
211:         case op
212:         when '||''||'
213:           super(:+, args)
214:         when :ILIKE
215:           super(:LIKE, args)
216:         when "NOT ILIKE""NOT ILIKE"
217:           super("NOT LIKE""NOT LIKE", args)
218:         else
219:           super(op, args)
220:         end
221:       end

MSSQL doesn‘t support the SQL standard CURRENT_DATE or CURRENT_TIME

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 224
224:       def constant_sql(constant)
225:         CONSTANT_MAP[constant] || super
226:       end

Disable the use of INSERT OUTPUT

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 229
229:       def disable_insert_output
230:         clone(:disable_insert_output=>true)
231:       end

Disable the use of INSERT OUTPUT, modifying the receiver

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 234
234:       def disable_insert_output!
235:         mutation_method(:disable_insert_output)
236:       end

When returning all rows, if an offset is used, delete the row_number column before yielding the row.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 240
240:       def fetch_rows(sql, &block)
241:         @opts[:offset] ? super(sql){|r| r.delete(row_number_column); yield r} : super(sql, &block)
242:       end

MSSQL uses the CONTAINS keyword for full text search

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 245
245:       def full_text_search(cols, terms, opts = {})
246:         filter("CONTAINS (#{literal(cols)}, #{literal(terms)})")
247:       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 250
250:       def insert_select(*values)
251:         return unless supports_output_clause?
252:         naked.clone(default_server_opts(:sql=>output(nil, [:inserted.*]).insert_sql(*values))).single_record unless opts[:disable_insert_output]
253:       end

Specify a table for a SELECT … INTO query.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 256
256:       def into(table)
257:         clone(:into => table)
258:       end

MSSQL uses a UNION ALL statement to insert multiple values at once.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 261
261:       def multi_insert_sql(columns, values)
262:         [insert_sql(columns, LiteralString.new(values.map {|r| "SELECT #{expression_list(r)}" }.join(" UNION ALL ")))]
263:       end

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

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 266
266:       def nolock
267:         lock_style(:dirty)
268:       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, [:deleted__id, :deleted__name])
  dataset.output(:output_table, :id => :inserted__id, :name => :inserted__name)

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 282
282:       def output(into, values)
283:         raise(Error, "SQL Server versions 2000 and earlier do not support the OUTPUT clause") unless supports_output_clause?
284:         output = {}
285:         case values
286:           when Hash
287:             output[:column_list], output[:select_list] = values.keys, values.values
288:           when Array
289:             output[:select_list] = values
290:         end
291:         output[:into] = into
292:         clone({:output => output})
293:       end

An output method that modifies the receiver.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 296
296:       def output!(into, values)
297:         mutation_method(:output, into, values)
298:       end

MSSQL uses [] to quote identifiers

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 301
301:       def quoted_identifier(name)
302:         "[#{name}]"
303:       end

MSSQL Requires the use of the ROW_NUMBER window function to emulate an offset. This implementation requires MSSQL 2005 or greater (offset can‘t be emulated well in MSSQL 2000).

The implementation is ugly, cloning the current dataset and modifying the clone to add a ROW_NUMBER window function (and some other things), then using the modified clone in a subselect which is selected from.

If offset is used, an order must be provided, because the use of ROW_NUMBER requires an order.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 315
315:       def select_sql
316:         return super unless o = @opts[:offset]
317:         raise(Error, 'MSSQL requires an order be provided if using an offset') unless order = @opts[:order]
318:         dsa1 = dataset_alias(1)
319:         rn = row_number_column
320:         subselect_sql(unlimited.
321:           unordered.
322:           select_append{ROW_NUMBER(:over, :order=>order){}.as(rn)}.
323:           from_self(:alias=>dsa1).
324:           limit(@opts[:limit]).
325:           where(SQL::Identifier.new(rn) > o))
326:       end

The version of the database server.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 329
329:       def server_version
330:         db.server_version(@opts[:server])
331:       end

Microsoft SQL Server does not support INTERSECT or EXCEPT

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 334
334:       def supports_intersect_except?
335:         false
336:       end

MSSQL does not support IS TRUE

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 339
339:       def supports_is_true?
340:         false
341:       end

MSSQL doesn‘t support JOIN USING

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 344
344:       def supports_join_using?
345:         false
346:       end

MSSQL 2005+ supports modifying joined datasets

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 349
349:       def supports_modifying_joins?
350:         true
351:       end

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

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 354
354:       def supports_multiple_column_in?
355:         false
356:       end

Only 2005+ supports the output clause.

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 359
359:       def supports_output_clause?
360:         server_version >= 9000000
361:       end

MSSQL 2005+ supports window functions

[Source]

     # File lib/sequel/adapters/shared/mssql.rb, line 364
364:       def supports_window_functions?
365:         true
366:       end

[Validate]