Module: Sequel::DB2::DatasetMethods

Includes:
EmulateOffsetWithRowNumber
Included in:
IBMDB::Dataset, JDBC::DB2::Dataset
Defined in:
lib/sequel/adapters/shared/db2.rb

Constant Summary collapse

BITWISE_METHOD_MAP =

.freeze # SEQUEL5

{:& =>:BITAND, :| => :BITOR, :^ => :BITXOR, :'B~'=>:BITNOT}
PAREN_CLOSE =
')'.freeze
PAREN_OPEN =
'('.freeze
BOOL_TRUE =
'1'.freeze
BOOL_FALSE =
'0'.freeze
CAST_STRING_OPEN =
"RTRIM(CHAR(".freeze
CAST_STRING_CLOSE =
"))".freeze
FETCH_FIRST_ROW_ONLY =
" FETCH FIRST ROW ONLY".freeze
FETCH_FIRST =
" FETCH FIRST ".freeze
ROWS_ONLY =
" ROWS ONLY".freeze
EMPTY_FROM_TABLE =
' FROM "SYSIBM"."SYSDUMMY1"'.freeze
HSTAR =
"H*".freeze
BLOB_OPEN =
"BLOB(X'".freeze
BLOB_CLOSE =
"')".freeze
EMULATED_FUNCTION_MAP =
{:char_length=>'length'.freeze}

Instance Method Summary collapse

Methods included from EmulateOffsetWithRowNumber

#empty?, #select_sql, #supports_offsets_in_correlated_subqueries?

Instance Method Details

#cast_sql_append(sql, expr, type) ⇒ Object

DB2 casts strings using RTRIM and CHAR instead of VARCHAR.



321
322
323
324
325
326
327
328
329
# File 'lib/sequel/adapters/shared/db2.rb', line 321

def cast_sql_append(sql, expr, type)
  if(type == String)
    sql << "RTRIM(CHAR("
    literal_append(sql, expr)
    sql << "))"
  else
    super
  end
end

#complex_expression_sql_append(sql, op, args) ⇒ Object



331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
# File 'lib/sequel/adapters/shared/db2.rb', line 331

def complex_expression_sql_append(sql, op, args)
  case op
  when :&, :|, :^, :%, :<<, :>>
    complex_expression_emulate_append(sql, op, args)
  when :'B~'
    literal_append(sql, SQL::Function.new(:BITNOT, *args))
  when :extract
    sql << args[0].to_s
    sql << '('
    literal_append(sql, args[1])
    sql << ')'
  else
    super
  end
end

#quote_identifiers?Boolean

Returns:

  • (Boolean)


347
348
349
# File 'lib/sequel/adapters/shared/db2.rb', line 347

def quote_identifiers?
  @opts.fetch(:quote_identifiers, false)
end

#supports_cte?(type = :select) ⇒ Boolean

Returns:

  • (Boolean)


351
352
353
# File 'lib/sequel/adapters/shared/db2.rb', line 351

def supports_cte?(type=:select)
  type == :select
end

#supports_group_cube?Boolean

DB2 supports GROUP BY CUBE

Returns:

  • (Boolean)


356
357
358
# File 'lib/sequel/adapters/shared/db2.rb', line 356

def supports_group_cube?
  true
end

#supports_group_rollup?Boolean

DB2 supports GROUP BY ROLLUP

Returns:

  • (Boolean)


361
362
363
# File 'lib/sequel/adapters/shared/db2.rb', line 361

def supports_group_rollup?
  true
end

#supports_grouping_sets?Boolean

DB2 supports GROUPING SETS

Returns:

  • (Boolean)


366
367
368
# File 'lib/sequel/adapters/shared/db2.rb', line 366

def supports_grouping_sets?
  true
end

#supports_is_true?Boolean

DB2 does not support IS TRUE.

Returns:

  • (Boolean)


371
372
373
# File 'lib/sequel/adapters/shared/db2.rb', line 371

def supports_is_true?
  false
end

#supports_lateral_subqueries?Boolean

DB2 supports lateral subqueries

Returns:

  • (Boolean)


376
377
378
# File 'lib/sequel/adapters/shared/db2.rb', line 376

def supports_lateral_subqueries?
  true
end

#supports_multiple_column_in?Boolean

DB2 does not support multiple columns in IN.

Returns:

  • (Boolean)


381
382
383
# File 'lib/sequel/adapters/shared/db2.rb', line 381

def supports_multiple_column_in?
  false
end

#supports_select_all_and_column?Boolean

DB2 only allows * in SELECT if it is the only thing being selected.

Returns:

  • (Boolean)


386
387
388
# File 'lib/sequel/adapters/shared/db2.rb', line 386

def supports_select_all_and_column?
  false
end

#supports_timestamp_usecs?Boolean

DB2 does not support fractional seconds in timestamps.

Returns:

  • (Boolean)


391
392
393
# File 'lib/sequel/adapters/shared/db2.rb', line 391

def supports_timestamp_usecs?
  false
end

#supports_where_true?Boolean

DB2 does not support WHERE 1.

Returns:

  • (Boolean)


401
402
403
# File 'lib/sequel/adapters/shared/db2.rb', line 401

def supports_where_true?
  false
end

#supports_window_functions?Boolean

DB2 supports window functions

Returns:

  • (Boolean)


396
397
398
# File 'lib/sequel/adapters/shared/db2.rb', line 396

def supports_window_functions?
  true
end