Sequel
extends Array
to add methods to implement the SQL DSL. Most of these methods require that the array not be empty and that it must consist solely of other arrays that have exactly two elements.
Methods
Public Instance
Public Instance methods
Return a Sequel::SQL::CaseExpression
with this array as the conditions and the given default value and expression.
[[{a: [2,3]}, 1]].case(0) # SQL: CASE WHEN (a IN (2, 3)) THEN 1 ELSE 0 END [[:a, 1], [:b, 2]].case(:d, :c) # SQL: CASE c WHEN a THEN 1 WHEN b THEN 2 ELSE d END
# File lib/sequel/extensions/core_extensions.rb 35 def case(*args) 36 ::Sequel::SQL::CaseExpression.new(self, *args) 37 end
Return a PGArray proxy to the receiver, using a specific database type if given. This is mostly useful as a short cut for creating PGArray objects that didn’t come from the database.
# File lib/sequel/extensions/pg_array.rb 541 def pg_array(type=nil) 542 Sequel::Postgres::PGArray.new(self, type) 543 end
Return a Sequel::Postgres::JSONArray
proxy to the receiver. This is mostly useful as a short cut for creating JSONArray objects that didn’t come from the database.
# File lib/sequel/extensions/pg_json.rb 592 def pg_json 593 Sequel::Postgres::JSONArray.new(self) 594 end
Return a Sequel::Postgres::JSONArray
proxy to the receiver. This is mostly useful as a short cut for creating JSONArray objects that didn’t come from the database.
# File lib/sequel/extensions/pg_json.rb 599 def pg_jsonb 600 Sequel::Postgres::JSONBArray.new(self) 601 end
Wraps the receiver in an anonymous Sequel::Postgres::PGRow::ArrayRow
instance.
# File lib/sequel/extensions/pg_row.rb 568 def pg_row 569 Sequel::Postgres::PGRow::ArrayRow.new(self) 570 end
Return a Sequel::SQL::BooleanExpression
created from this array, matching all of the conditions. Rarely do you need to call this explicitly, as Sequel
generally assumes that arrays of two element arrays specify this type of condition. One case where it can be necessary to use this is if you are using the object as a value in a filter hash and want to use the = operator instead of the IN operator (which is used by default for arrays of two element arrays).
[[:a, true]].sql_expr # SQL: (a IS TRUE) [[:a, 1], [:b, [2, 3]]].sql_expr # SQL: ((a = 1) AND (b IN (2, 3)))
# File lib/sequel/extensions/core_extensions.rb 61 def sql_expr 62 Sequel[self] 63 end
Return a Sequel::SQL::BooleanExpression
created from this array, matching none of the conditions.
[[:a, true]].sql_negate # SQL: (a IS NOT TRUE) [[:a, 1], [:b, [2, 3]]].sql_negate # SQL: ((a != 1) AND (b NOT IN (2, 3)))
# File lib/sequel/extensions/core_extensions.rb 70 def sql_negate 71 Sequel.negate(self) 72 end
Return a Sequel::SQL::BooleanExpression
created from this array, matching any of the conditions.
[[:a, true]].sql_or # SQL: (a IS TRUE) [[:a, 1], [:b, [2, 3]]].sql_or # SQL: ((a = 1) OR (b IN (2, 3)))
# File lib/sequel/extensions/core_extensions.rb 79 def sql_or 80 Sequel.or(self) 81 end
Return a Sequel::SQL::StringExpression
representing an SQL string made up of the concatenation of this array’s elements. If an argument is passed it is used in between each element of the array in the SQL concatenation.
[:a].sql_string_join # SQL: a [:a, :b].sql_string_join # SQL: (a || b) [:a, 'b'].sql_string_join # SQL: (a || 'b') ['a', :b].sql_string_join(' ') # SQL: ('a' || ' ' || b)
# File lib/sequel/extensions/core_extensions.rb 92 def sql_string_join(joiner=nil) 93 Sequel.join(self, joiner) 94 end
Return a Sequel::SQL::ValueList
created from this array. Used if this array contains all two element arrays and you want it treated as an SQL value list (IN predicate) instead of as a conditions specifier (similar to a hash). This is not necessary if you are using this array as a value in a filter, but may be necessary if you are using it as a value with placeholder SQL:
DB[:a].where([:a, :b]=>[[1, 2], [3, 4]]) # SQL: ((a, b) IN ((1, 2), (3, 4))) DB[:a].where('(a, b) IN ?', [[1, 2], [3, 4]]) # SQL: ((a, b) IN ((1 = 2) AND (3 = 4))) DB[:a].where('(a, b) IN ?', [[1, 2], [3, 4]].sql_value_list) # SQL: ((a, b) IN ((1, 2), (3, 4)))
# File lib/sequel/extensions/core_extensions.rb 48 def sql_value_list 49 ::Sequel::SQL::ValueList.new(self) 50 end
Return a Sequel::SQL::BooleanExpression
created from this array, not matching all of the conditions.
~[[:a, true]] # SQL: (a IS NOT TRUE) ~[[:a, 1], [:b, [2, 3]]] # SQL: ((a != 1) OR (b NOT IN (2, 3)))
# File lib/sequel/extensions/core_extensions.rb 26 def ~ 27 Sequel.~(self) 28 end