module Sequel::Oracle

Public Instance Methods

complex_expression_sql_append(sql, op, args) click to toggle source
Calls superclass method
# File lib/sequel/adapters/shared/oracle.rb, line 273
def complex_expression_sql_append(sql, op, args)
  case op
  when :&
    complex_expression_arg_pairs_append(sql, args, &BITAND_PROC)
  when :|
    complex_expression_arg_pairs_append(sql, args){|a, b| Sequel.lit(["(", " - ", " + ", ")"], a, complex_expression_arg_pairs([a, b], &BITAND_PROC), b)}
  when :^
    complex_expression_arg_pairs_append(sql, args) do |*x|
      s1 = complex_expression_arg_pairs(x){|a, b| Sequel.lit(["(", " - ", " + ", ")"], a, complex_expression_arg_pairs([a, b], &BITAND_PROC), b)}
      s2 = complex_expression_arg_pairs(x, &BITAND_PROC)
      Sequel.lit(["(", " - ", ")"], s1, s2)
    end
  when :%, :<<, :>>, :'B~'
    complex_expression_emulate_append(sql, op, args)
  else
    super
  end
end
constant_sql_append(sql, c) click to toggle source

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.

Calls superclass method
# File lib/sequel/adapters/shared/oracle.rb, line 295
def constant_sql_append(sql, c)
  if c == :CURRENT_TIME
    super(sql, :CURRENT_TIMESTAMP)
  else
    super
  end
end
empty?() click to toggle source

Use a custom expression with EXISTS to determine whether a dataset is empty.

# File lib/sequel/adapters/shared/oracle.rb, line 311
def empty?
  db[:dual].where(@opts[:offset] ? exists : unordered.exists).get(1) == nil
end
except(dataset, opts=OPTS) click to toggle source

Oracle uses MINUS instead of EXCEPT, and doesn't support EXCEPT ALL

# File lib/sequel/adapters/shared/oracle.rb, line 304
def except(dataset, opts=OPTS)
  raise(Sequel::Error, "EXCEPT ALL not supported") if opts[:all]
  compound_clone(:minus, dataset, opts)
end
recursive_cte_requires_column_aliases?() click to toggle source

Oracle requires recursive CTEs to have column aliases.

# File lib/sequel/adapters/shared/oracle.rb, line 359
def recursive_cte_requires_column_aliases?
  true
end
requires_sql_standard_datetimes?() click to toggle source

Oracle requires SQL standard datetimes

# File lib/sequel/adapters/shared/oracle.rb, line 316
def requires_sql_standard_datetimes?
  true
end
select_sql() click to toggle source

Handle LIMIT by using a unlimited subselect filtered with ROWNUM.

Calls superclass method
# File lib/sequel/adapters/shared/oracle.rb, line 328
def select_sql
  return super if @opts[:sql]
  if o = @opts[:offset]
    columns = clone(:append_sql=>'', :placeholder_literal_null=>true).columns
    dsa1 = dataset_alias(1)
    rn = row_number_column
    limit = @opts[:limit]
    ds = unlimited.
      from_self(:alias=>dsa1).
      select_append(ROW_NUMBER_EXPRESSION.as(rn)).
      from_self(:alias=>dsa1).
      select(*columns).
      where(SQL::Identifier.new(rn) > o)
    ds = ds.where(SQL::Identifier.new(rn) <= Sequel.+(o, limit)) if limit
    sql = @opts[:append_sql] || ''
    subselect_sql_append(sql, ds)
    sql
  elsif limit = @opts[:limit]
    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
sequence(s) click to toggle source

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 323
def sequence(s)
  clone(:sequence=>s)
end
supports_cte?(type=:select) click to toggle source
# File lib/sequel/adapters/shared/oracle.rb, line 363
def supports_cte?(type=:select)
  type == :select
end
supports_derived_column_lists?() click to toggle source

Oracle does not support derived column lists

# File lib/sequel/adapters/shared/oracle.rb, line 368
def supports_derived_column_lists?
  false
end
supports_group_cube?() click to toggle source

Oracle supports GROUP BY CUBE

# File lib/sequel/adapters/shared/oracle.rb, line 373
def supports_group_cube?
  true
end
supports_group_rollup?() click to toggle source

Oracle supports GROUP BY ROLLUP

# File lib/sequel/adapters/shared/oracle.rb, line 378
def supports_group_rollup?
  true
end
supports_intersect_except_all?() click to toggle source

Oracle does not support INTERSECT ALL or EXCEPT ALL

# File lib/sequel/adapters/shared/oracle.rb, line 383
def supports_intersect_except_all?
  false
end
supports_is_true?() click to toggle source

Oracle does not support IS TRUE.

# File lib/sequel/adapters/shared/oracle.rb, line 388
def supports_is_true?
  false
end
supports_limits_in_correlated_subqueries?() click to toggle source

Oracle does not support limits in correlated subqueries.

# File lib/sequel/adapters/shared/oracle.rb, line 393
def supports_limits_in_correlated_subqueries?
  false
end
supports_offsets_in_correlated_subqueries?() click to toggle source

Oracle does not support offsets in correlated subqueries.

# File lib/sequel/adapters/shared/oracle.rb, line 398
def supports_offsets_in_correlated_subqueries?
  false
end
supports_select_all_and_column?() click to toggle source

Oracle does not support SELECT *, column

# File lib/sequel/adapters/shared/oracle.rb, line 403
def supports_select_all_and_column?
  false
end
supports_timestamp_timezones?() click to toggle source

Oracle supports timezones in literal timestamps.

# File lib/sequel/adapters/shared/oracle.rb, line 408
def supports_timestamp_timezones?
  true
end
supports_where_true?() click to toggle source

Oracle does not support WHERE 'Y' for WHERE TRUE.

# File lib/sequel/adapters/shared/oracle.rb, line 413
def supports_where_true?
  false
end
supports_window_functions?() click to toggle source

Oracle supports window functions

# File lib/sequel/adapters/shared/oracle.rb, line 418
def supports_window_functions?
  true
end

Private Instance Methods

as_sql_append(sql, aliaz, column_aliases=nil) click to toggle source

Oracle doesn't support the use of AS when aliasing a dataset. It doesn't require the use of AS anywhere, so this disables it in all cases.

# File lib/sequel/adapters/shared/oracle.rb, line 426
def as_sql_append(sql, aliaz, column_aliases=nil)
  raise Error, "oracle does not support derived column lists" if column_aliases
  sql << SPACE
  quote_identifier_append(sql, aliaz)
end
default_timestamp_format() click to toggle source

The strftime format to use when literalizing the time.

# File lib/sequel/adapters/shared/oracle.rb, line 433
def default_timestamp_format
  TIMESTAMP_FORMAT
end
empty_from_sql() click to toggle source
# File lib/sequel/adapters/shared/oracle.rb, line 437
def empty_from_sql
  DUAL
end
emulate_function?(name) click to toggle source

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/oracle.rb, line 445
def emulate_function?(name)
  name == :char_length
end
emulate_function_sql_append(sql, f) click to toggle source

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 454
def emulate_function_sql_append(sql, f)
  if f.name == :char_length
    literal_append(sql, Sequel::SQL::Function.new(:length, Sequel.join([f.args.first, 'x'])) - 1)
  end
end
execute_insert(sql, opts=OPTS) click to toggle source

If this dataset is associated with a sequence, return the most recently inserted sequence value.

Calls superclass method
# File lib/sequel/adapters/shared/oracle.rb, line 462
def execute_insert(sql, opts=OPTS)
  f = @opts[:from]
  super(sql, {:table=>(f.first if f), :sequence=>@opts[:sequence]}.merge(opts))
end
format_timestamp_offset(hour, minute) click to toggle source

Use a colon for the timestamp offset, since Oracle appears to require it.

# File lib/sequel/adapters/shared/oracle.rb, line 468
def format_timestamp_offset(hour, minute)
  sprintf(TIMESTAMP_OFFSET_FORMAT, hour, minute)
end
insert_supports_empty_values?() click to toggle source

Oracle doesn't support empty values when inserting.

# File lib/sequel/adapters/shared/oracle.rb, line 473
def insert_supports_empty_values?
  false
end
literal_blob_append(sql, v) click to toggle source

Use string in hex format for blob data.

# File lib/sequel/adapters/shared/oracle.rb, line 478
def literal_blob_append(sql, v)
  sql << APOS << v.unpack(HSTAR).first << APOS
end
literal_false() click to toggle source

Oracle uses 'N' for false values.

# File lib/sequel/adapters/shared/oracle.rb, line 483
def literal_false
  BOOL_FALSE
end
literal_string_append(sql, v) click to toggle source

Oracle uses the SQL standard of only doubling ' inside strings.

# File lib/sequel/adapters/shared/oracle.rb, line 488
def literal_string_append(sql, v)
  sql << APOS << v.gsub(APOS_RE, DOUBLE_APOS) << APOS
end
literal_true() click to toggle source

Oracle uses 'Y' for true values.

# File lib/sequel/adapters/shared/oracle.rb, line 493
def literal_true
  BOOL_TRUE
end
multi_insert_sql_strategy() click to toggle source

Oracle can insert multiple rows using a UNION

# File lib/sequel/adapters/shared/oracle.rb, line 498
def multi_insert_sql_strategy
  :union
end
supports_quoted_function_names?() click to toggle source

Oracle supports quoted function names.

# File lib/sequel/adapters/shared/oracle.rb, line 503
def supports_quoted_function_names?
  true
end