From 1a246f71616cf246a75ef6cbdb56032e43d4e643 Mon Sep 17 00:00:00 2001 From: Viacheslav Petrenko Date: Mon, 27 Dec 2010 18:16:18 +0200 Subject: Patched Arel v2.0.6 to support MSSQL SQL queries. Based on work of James Abley (https://github.com/jabley/arel). --- lib/arel/nodes.rb | 2 ++ lib/arel/nodes/limit.rb | 7 +++++++ lib/arel/nodes/select_core.rb | 3 ++- lib/arel/nodes/top.rb | 6 ++++++ lib/arel/select_manager.rb | 5 +++-- lib/arel/visitors.rb | 3 +++ lib/arel/visitors/mssql.rb | 16 ++++++++++++++++ lib/arel/visitors/mysql.rb | 2 +- lib/arel/visitors/sqlite.rb | 2 +- lib/arel/visitors/to_sql.rb | 15 +++++++++++++-- 10 files changed, 54 insertions(+), 7 deletions(-) create mode 100644 lib/arel/nodes/limit.rb create mode 100644 lib/arel/nodes/top.rb create mode 100644 lib/arel/visitors/mssql.rb (limited to 'lib') diff --git a/lib/arel/nodes.rb b/lib/arel/nodes.rb index c454152d0d..db2f22750a 100644 --- a/lib/arel/nodes.rb +++ b/lib/arel/nodes.rb @@ -24,6 +24,8 @@ require 'arel/nodes/function' require 'arel/nodes/count' require 'arel/nodes/values' require 'arel/nodes/offset' +require 'arel/nodes/limit' +require 'arel/nodes/top' require 'arel/nodes/sum' require 'arel/nodes/exists' require 'arel/nodes/max' diff --git a/lib/arel/nodes/limit.rb b/lib/arel/nodes/limit.rb new file mode 100644 index 0000000000..68ea95daf5 --- /dev/null +++ b/lib/arel/nodes/limit.rb @@ -0,0 +1,7 @@ +module Arel + module Nodes + class Limit < Arel::Nodes::Unary + end + end +end + diff --git a/lib/arel/nodes/select_core.rb b/lib/arel/nodes/select_core.rb index acc6bb9815..501a2aaf7c 100644 --- a/lib/arel/nodes/select_core.rb +++ b/lib/arel/nodes/select_core.rb @@ -1,10 +1,11 @@ module Arel module Nodes class SelectCore < Arel::Nodes::Node - attr_accessor :froms, :projections, :wheres, :groups + attr_accessor :top, :froms, :projections, :wheres, :groups attr_accessor :having def initialize + @top = nil @froms = nil @projections = [] @wheres = [] diff --git a/lib/arel/nodes/top.rb b/lib/arel/nodes/top.rb new file mode 100644 index 0000000000..56e2e97e8d --- /dev/null +++ b/lib/arel/nodes/top.rb @@ -0,0 +1,6 @@ +module Arel + module Nodes + class Top < Arel::Nodes::Unary + end + end +end diff --git a/lib/arel/select_manager.rb b/lib/arel/select_manager.rb index 10d23378ae..cb656d5340 100644 --- a/lib/arel/select_manager.rb +++ b/lib/arel/select_manager.rb @@ -10,7 +10,7 @@ module Arel end def taken - @ast.limit + @ast.limit && @ast.limit.expr end def constraints @@ -131,7 +131,8 @@ module Arel end def take limit - @ast.limit = limit + @ast.limit = Nodes::Limit.new(limit) + @ctx.top = Nodes::Top.new(limit) self end diff --git a/lib/arel/visitors.rb b/lib/arel/visitors.rb index 2b0a06d534..8410b2b912 100644 --- a/lib/arel/visitors.rb +++ b/lib/arel/visitors.rb @@ -4,6 +4,7 @@ require 'arel/visitors/to_sql' require 'arel/visitors/sqlite' require 'arel/visitors/postgresql' require 'arel/visitors/mysql' +require 'arel/visitors/mssql' require 'arel/visitors/oracle' require 'arel/visitors/join_sql' require 'arel/visitors/where_sql' @@ -16,6 +17,8 @@ module Arel 'postgresql' => Arel::Visitors::PostgreSQL, 'mysql' => Arel::Visitors::MySQL, 'mysql2' => Arel::Visitors::MySQL, + 'mssql' => Arel::Visitors::MSSQL, + 'sqlserver' => Arel::Visitors::MSSQL, 'oracle_enhanced' => Arel::Visitors::Oracle, 'sqlite' => Arel::Visitors::SQLite, 'sqlite3' => Arel::Visitors::SQLite, diff --git a/lib/arel/visitors/mssql.rb b/lib/arel/visitors/mssql.rb new file mode 100644 index 0000000000..9b0e77c19b --- /dev/null +++ b/lib/arel/visitors/mssql.rb @@ -0,0 +1,16 @@ +module Arel + module Visitors + class MSSQL < Arel::Visitors::ToSql + private + + def visit_Arel_Nodes_Limit o + "" + end + + def visit_Arel_Nodes_Top o + "TOP #{visit o.expr}" + end + + end + end +end diff --git a/lib/arel/visitors/mysql.rb b/lib/arel/visitors/mysql.rb index ace8fb0979..b37d76f710 100644 --- a/lib/arel/visitors/mysql.rb +++ b/lib/arel/visitors/mysql.rb @@ -10,7 +10,7 @@ module Arel # :'( # http://dev.mysql.com/doc/refman/5.0/en/select.html#id3482214 def visit_Arel_Nodes_SelectStatement o - o.limit = 18446744073709551615 if o.offset && !o.limit + o.limit = Arel::Nodes::Limit.new(18446744073709551615) if o.offset && !o.limit super end diff --git a/lib/arel/visitors/sqlite.rb b/lib/arel/visitors/sqlite.rb index c45160851d..237ae913bb 100644 --- a/lib/arel/visitors/sqlite.rb +++ b/lib/arel/visitors/sqlite.rb @@ -3,7 +3,7 @@ module Arel class SQLite < Arel::Visitors::ToSql private def visit_Arel_Nodes_SelectStatement o - o.limit = -1 if o.offset && !o.limit + o.limit = Arel::Nodes::Limit.new(-1) if o.offset && !o.limit super end end diff --git a/lib/arel/visitors/to_sql.rb b/lib/arel/visitors/to_sql.rb index a2105d7043..7435e41561 100644 --- a/lib/arel/visitors/to_sql.rb +++ b/lib/arel/visitors/to_sql.rb @@ -76,7 +76,7 @@ module Arel [ o.cores.map { |x| visit_Arel_Nodes_SelectCore x }.join, ("ORDER BY #{o.orders.map { |x| visit x }.join(', ')}" unless o.orders.empty?), - ("LIMIT #{visit o.limit}" if o.limit), + (visit(o.limit) if o.limit), (visit(o.offset) if o.offset), (visit(o.lock) if o.lock), ].compact.join ' ' @@ -84,7 +84,9 @@ module Arel def visit_Arel_Nodes_SelectCore o [ - "SELECT #{o.projections.map { |x| visit x }.join ', '}", + "SELECT", + (visit(o.top) if o.top), + "#{o.projections.map { |x| visit x }.join ', '}", ("FROM #{visit o.froms}" if o.froms), ("WHERE #{o.wheres.map { |x| visit x }.join ' AND ' }" unless o.wheres.empty?), ("GROUP BY #{o.groups.map { |x| visit x }.join ', ' }" unless o.groups.empty?), @@ -100,6 +102,15 @@ module Arel "OFFSET #{visit o.expr}" end + def visit_Arel_Nodes_Limit o + "LIMIT #{visit o.expr}" + end + + # FIXME: this does nothing on most databases, but does on MSSQL + def visit_Arel_Nodes_Top o + "" + end + # FIXME: this does nothing on SQLLite3, but should do things on other # databases. def visit_Arel_Nodes_Lock o -- cgit v1.2.3