diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/arel/visitors/mssql.rb | 32 |
1 files changed, 22 insertions, 10 deletions
diff --git a/lib/arel/visitors/mssql.rb b/lib/arel/visitors/mssql.rb index ef0b78058e..cc5e74af1f 100644 --- a/lib/arel/visitors/mssql.rb +++ b/lib/arel/visitors/mssql.rb @@ -1,6 +1,14 @@ module Arel module Visitors class MSSQL < Arel::Visitors::ToSql + class RowNumber + attr_reader :children + + def initialize node + @children = node + end + end + private # `top` wouldn't really work here. I.e. User.select("distinct first_name").limit(10) would generate @@ -10,21 +18,23 @@ module Arel "" end + def visit_Arel_Visitors_MSSQL_RowNumber o + "ROW_NUMBER() OVER (ORDER BY #{o.children.map { |x| visit x }.join ', '}) as _row_num" + end + def visit_Arel_Nodes_SelectStatement o if !o.limit && !o.offset return super o end - select_order_by = "ORDER BY #{o.orders.map { |x| visit x }.join(', ')}" unless o.orders.empty? - is_select_count = false sql = o.cores.map { |x| - core_order_by = select_order_by || determine_order_by(x) + core_order_by = row_num_literal determine_order_by(o.orders, x) if select_count? x - x.projections = [row_num_literal(core_order_by)] + x.projections = [core_order_by] is_select_count = true else - x.projections << row_num_literal(core_order_by) + x.projections << core_order_by end visit_Arel_Nodes_SelectCore x @@ -46,16 +56,18 @@ module Arel end end - def determine_order_by x - unless x.groups.empty? - "ORDER BY #{x.groups.map { |g| visit g }.join ', ' }" + def determine_order_by orders, x + if orders.any? + orders + elsif x.groups.any? + x.groups else - "ORDER BY #{find_left_table_pk(x.froms)}" + [Arel.sql(find_left_table_pk(x.froms).to_s)] end end def row_num_literal order_by - Nodes::SqlLiteral.new("ROW_NUMBER() OVER (#{order_by}) as _row_num") + RowNumber.new order_by end def select_count? x |