diff options
Diffstat (limited to 'activerecord/lib/arel/visitors/mysql.rb')
-rw-r--r-- | activerecord/lib/arel/visitors/mysql.rb | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/activerecord/lib/arel/visitors/mysql.rb b/activerecord/lib/arel/visitors/mysql.rb new file mode 100644 index 0000000000..37bfb661f0 --- /dev/null +++ b/activerecord/lib/arel/visitors/mysql.rb @@ -0,0 +1,87 @@ +# frozen_string_literal: true + +module Arel # :nodoc: all + module Visitors + class MySQL < Arel::Visitors::ToSql + private + def visit_Arel_Nodes_Union(o, collector, suppress_parens = false) + unless suppress_parens + collector << "( " + end + + collector = case o.left + when Arel::Nodes::Union + visit_Arel_Nodes_Union o.left, collector, true + else + visit o.left, collector + end + + collector << " UNION " + + collector = case o.right + when Arel::Nodes::Union + visit_Arel_Nodes_Union o.right, collector, true + else + visit o.right, collector + end + + if suppress_parens + collector + else + collector << " )" + end + end + + def visit_Arel_Nodes_Bin(o, collector) + collector << "BINARY " + visit o.expr, collector + end + + ### + # :'( + # http://dev.mysql.com/doc/refman/5.0/en/select.html#id3482214 + def visit_Arel_Nodes_SelectStatement(o, collector) + if o.offset && !o.limit + o.limit = Arel::Nodes::Limit.new(18446744073709551615) + end + super + end + + def visit_Arel_Nodes_SelectCore(o, collector) + o.froms ||= Arel.sql("DUAL") + super + end + + def visit_Arel_Nodes_UpdateStatement(o, collector) + collector << "UPDATE " + collector = visit o.relation, collector + + unless o.values.empty? + collector << " SET " + collector = inject_join o.values, collector, ", " + end + + unless o.wheres.empty? + collector << " WHERE " + collector = inject_join o.wheres, collector, " AND " + end + + unless o.orders.empty? + collector << " ORDER BY " + collector = inject_join o.orders, collector, ", " + end + + maybe_visit o.limit, collector + end + + def visit_Arel_Nodes_Concat(o, collector) + collector << " CONCAT(" + visit o.left, collector + collector << ", " + visit o.right, collector + collector << ") " + collector + end + end + end +end |