# File lib/sequel/adapters/shared/oracle.rb, line 243 def complex_expression_sql_append(sql, op, args) case op when :& sql << complex_expression_arg_pairs(args){|a, b| "CAST(BITAND(#{literal(a)}, #{literal(b)}) AS INTEGER)"} when :| sql << complex_expression_arg_pairs(args){|a, b| "(#{literal(a)} - #{complex_expression_sql(:&, [a, b])} + #{literal(b)})"} when :^ sql << complex_expression_arg_pairs(args){|*x| "(#{complex_expression_sql(:|, x)} - #{complex_expression_sql(:&, x)})"} when :'B~' sql << BITCOMP_OPEN literal_append(sql, args.at(0)) sql << BITCOMP_CLOSE when :<< sql << complex_expression_arg_pairs(args){|a, b| "(#{literal(a)} * power(2, #{literal b}))"} when :>> sql << complex_expression_arg_pairs(args){|a, b| "(#{literal(a)} / power(2, #{literal b}))"} when :% sql << complex_expression_arg_pairs(args){|a, b| "MOD(#{literal(a)}, #{literal(b)})"} else super end end
Oracle doesn't support CURRENT_TIME, as it doesn't have a type for storing just time values without a date, so use CURRENT_TIMESTAMP in its place.
# File lib/sequel/adapters/shared/oracle.rb, line 269 def constant_sql_append(sql, c) if c == :CURRENT_TIME super(sql, :CURRENT_TIMESTAMP) else super end end
Use a custom expression with EXISTS to determine whether a dataset is empty.
# File lib/sequel/adapters/shared/oracle.rb, line 300 def empty? db[:dual].where(@opts[:offset] ? exists : unordered.exists).get(1) == nil end
Oracle treats empty strings like NULL values, and doesn't support char_length, so make char_length use length with a nonempty string. Unfortunately, as Oracle treats the empty string as NULL, there is no way to get trim to return an empty string instead of nil if the string only contains spaces.
# File lib/sequel/adapters/shared/oracle.rb, line 282 def emulated_function_sql_append(sql, f) case f.f when :char_length literal_append(sql, Sequel::SQL::Function.new(:length, Sequel.join([f.args.first, 'x'])) - 1) else super end end
Oracle uses MINUS instead of EXCEPT, and doesn't support EXCEPT ALL
# File lib/sequel/adapters/shared/oracle.rb, line 292 def except(dataset, opts={}) opts = {:all=>opts} unless opts.is_a?(Hash) raise(Sequel::Error, "EXCEPT ALL not supported") if opts[:all] compound_clone(:minus, dataset, opts) end
Oracle requires recursive CTEs to have column aliases.
# File lib/sequel/adapters/shared/oracle.rb, line 332 def recursive_cte_requires_column_aliases? true end
Handle LIMIT by using a unlimited subselect filtered with ROWNUM.
# File lib/sequel/adapters/shared/oracle.rb, line 317 def select_sql if (limit = @opts[:limit]) && !@opts[:sql] ds = clone(:limit=>nil) # Lock doesn't work in subselects, so don't use a subselect when locking. # Don't use a subselect if custom SQL is used, as it breaks somethings. ds = ds.from_self unless @opts[:lock] sql = @opts[:append_sql] || '' subselect_sql_append(sql, ds.where(SQL::ComplexExpression.new(:<=, ROW_NUMBER_EXPRESSION, limit))) sql else super end end
Create a copy of this dataset associated to the given sequence name, which will be used when calling insert to find the most recently inserted value for the sequence.
# File lib/sequel/adapters/shared/oracle.rb, line 312 def sequence(s) clone(:sequence=>s) end
Oracle supports GROUP BY CUBE
# File lib/sequel/adapters/shared/oracle.rb, line 337 def supports_group_cube? true end
Oracle supports GROUP BY ROLLUP
# File lib/sequel/adapters/shared/oracle.rb, line 342 def supports_group_rollup? true end
Oracle does not support INTERSECT ALL or EXCEPT ALL
# File lib/sequel/adapters/shared/oracle.rb, line 347 def supports_intersect_except_all? false end
Oracle does not support IS TRUE.
# File lib/sequel/adapters/shared/oracle.rb, line 352 def supports_is_true? false end
Oracle does not support SELECT *, column
# File lib/sequel/adapters/shared/oracle.rb, line 357 def supports_select_all_and_column? false end
Oracle supports timezones in literal timestamps.
# File lib/sequel/adapters/shared/oracle.rb, line 362 def supports_timestamp_timezones? true end
Oracle does not support WHERE 'Y' for WHERE TRUE.
# File lib/sequel/adapters/shared/oracle.rb, line 367 def supports_where_true? false end
Oracle supports window functions
# File lib/sequel/adapters/shared/oracle.rb, line 372 def supports_window_functions? true end