From bc0510c0027c28a2b45c8c51f75edaf40d6f4536 Mon Sep 17 00:00:00 2001
From: Aaron Patterson <aaron.patterson@gmail.com>
Date: Tue, 17 May 2011 18:01:35 -0400
Subject: do not cache sql literal values
---
lib/arel/visitors/to_sql.rb | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
(limited to 'lib/arel/visitors')
diff --git a/lib/arel/visitors/to_sql.rb b/lib/arel/visitors/to_sql.rb
index 312f92ea2f..29e965bef8 100644
--- a/lib/arel/visitors/to_sql.rb
+++ b/lib/arel/visitors/to_sql.rb
@@ -416,7 +416,8 @@ key on UpdateManager using UpdateManager#key=
end
def quote_table_name name
- @quoted_tables[name] ||= Arel::Nodes::SqlLiteral === name ? name : @connection.quote_table_name(name)
+ return name if Arel::Nodes::SqlLiteral === name
+ @quoted_tables[name] ||= @connection.quote_table_name(name)
end
def quote_column_name name
--
cgit v1.2.3
From be48ed3071fd6524d0145c4ad3faeb4aafe3eda3 Mon Sep 17 00:00:00 2001
From: arkadiy kraportov <arkadiyk@gmail.com>
Date: Thu, 9 Jun 2011 18:24:54 +0900
Subject: LIMIT and OFFSET support for MS SQL
---
lib/arel/visitors/mssql.rb | 78 ++++++++++++++++++++++++++++++++++++++++------
1 file changed, 69 insertions(+), 9 deletions(-)
(limited to 'lib/arel/visitors')
diff --git a/lib/arel/visitors/mssql.rb b/lib/arel/visitors/mssql.rb
index ea7ab6394c..713ad0f0f8 100644
--- a/lib/arel/visitors/mssql.rb
+++ b/lib/arel/visitors/mssql.rb
@@ -3,19 +3,79 @@ module Arel
class MSSQL < Arel::Visitors::ToSql
private
- def build_subselect key, o
- stmt = super
- core = stmt.cores.first
- core.top = Nodes::Top.new(o.limit.expr) if o.limit
- stmt
+ # `top` wouldn't really work here. I.e. User.select("distinct first_name").limit(10) would generate
+ # "select top 10 distinct first_name from users", which is invalid query! it should be
+ # "select distinct top 10 first_name from users"
+ def visit_Arel_Nodes_Top o
+ ""
end
- def visit_Arel_Nodes_Limit o
- ""
+ 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)
+ if select_count? x
+ x.projections = [row_num_literal(core_order_by)]
+ is_select_count = true
+ else
+ guard_against_select_constant! x
+ x.projections << row_num_literal(core_order_by)
+ end
+
+ visit_Arel_Nodes_SelectCore x
+ }.join
+
+ sql = "SELECT _t.* FROM (#{sql}) as _t WHERE #{get_offset_limit_clause(o)}"
+ # fixme count distinct wouldn't work with limit or offset
+ sql = "SELECT COUNT(1) as count_id FROM (#{sql}) AS subquery" if is_select_count
+ sql
end
- def visit_Arel_Nodes_Top o
- "TOP #{visit o.expr}"
+ def get_offset_limit_clause o
+ first_row = o.offset ? o.offset.expr.to_i + 1 : 1
+ last_row = o.limit ? o.limit.expr.to_i - 1 + first_row : nil
+ if last_row
+ " _row_num BETWEEN #{first_row} AND #{last_row}"
+ else
+ " _row_num >= #{first_row}"
+ end
+ end
+
+ def determine_order_by x
+ unless x.groups.empty?
+ "ORDER BY #{x.groups.map { |g| visit g }.join ', ' }"
+ else
+ "ORDER BY #{find_left_table_pk(x.froms)}"
+ end
+ end
+
+ def row_num_literal order_by
+ Nodes::SqlLiteral.new("ROW_NUMBER() OVER (#{order_by}) as _row_num")
+ end
+
+ def select_count? x
+ x.projections.length == 1 && Arel::Nodes::Count === x.projections.first
+ end
+
+ def guard_against_select_constant! x
+ # guard against .select(1) (i.e. validate_uniqueness uses it to minimize qry result set)
+ # todo it won't work for .select('a'), which is probably ok. 'coz of workaround: .select("'a' as a")
+ x.projections.map! do |p|
+ p.kind_of?(Fixnum) ? Nodes::SqlLiteral.new("#{p} as _fld_#{p}") : p
+ end
+ end
+
+ # fixme raise exception of there is no pk?
+ # fixme!! Table.primary_key will be depricated. What is the replacement??
+ def find_left_table_pk o
+ return visit o.primary_key if o.instance_of? Arel::Table
+ find_left_table_pk o.left if o.kind_of? Arel::Nodes::Join
end
end
--
cgit v1.2.3
From 3da816a77318d28617d0e12739d29d76e372a4f9 Mon Sep 17 00:00:00 2001
From: arkadiy kraportov <arkadiyk@gmail.com>
Date: Fri, 10 Jun 2011 12:47:55 +0900
Subject: remove unnecessary guarding agains literal
---
lib/arel/visitors/mssql.rb | 10 ----------
1 file changed, 10 deletions(-)
(limited to 'lib/arel/visitors')
diff --git a/lib/arel/visitors/mssql.rb b/lib/arel/visitors/mssql.rb
index 713ad0f0f8..23dc06a936 100644
--- a/lib/arel/visitors/mssql.rb
+++ b/lib/arel/visitors/mssql.rb
@@ -24,7 +24,6 @@ module Arel
x.projections = [row_num_literal(core_order_by)]
is_select_count = true
else
- guard_against_select_constant! x
x.projections << row_num_literal(core_order_by)
end
@@ -63,21 +62,12 @@ module Arel
x.projections.length == 1 && Arel::Nodes::Count === x.projections.first
end
- def guard_against_select_constant! x
- # guard against .select(1) (i.e. validate_uniqueness uses it to minimize qry result set)
- # todo it won't work for .select('a'), which is probably ok. 'coz of workaround: .select("'a' as a")
- x.projections.map! do |p|
- p.kind_of?(Fixnum) ? Nodes::SqlLiteral.new("#{p} as _fld_#{p}") : p
- end
- end
-
# fixme raise exception of there is no pk?
# fixme!! Table.primary_key will be depricated. What is the replacement??
def find_left_table_pk o
return visit o.primary_key if o.instance_of? Arel::Table
find_left_table_pk o.left if o.kind_of? Arel::Nodes::Join
end
-
end
end
end
--
cgit v1.2.3
From ba3578a22f824da3478b6dceb100deb9f41a56e9 Mon Sep 17 00:00:00 2001
From: Ernie Miller <ernie@metautonomo.us>
Date: Tue, 14 Jun 2011 17:43:22 -0400
Subject: Break Ordering into Ascending/Descending nodes, allow reversal
---
lib/arel/visitors/depth_first.rb | 2 +-
lib/arel/visitors/dot.rb | 1 -
lib/arel/visitors/to_sql.rb | 8 ++++++--
3 files changed, 7 insertions(+), 4 deletions(-)
(limited to 'lib/arel/visitors')
diff --git a/lib/arel/visitors/depth_first.rb b/lib/arel/visitors/depth_first.rb
index 914b2d1999..6f9385de1b 100644
--- a/lib/arel/visitors/depth_first.rb
+++ b/lib/arel/visitors/depth_first.rb
@@ -22,6 +22,7 @@ module Arel
alias :visit_Arel_Nodes_Not :unary
alias :visit_Arel_Nodes_Offset :unary
alias :visit_Arel_Nodes_On :unary
+ alias :visit_Arel_Nodes_Ordering :unary
alias :visit_Arel_Nodes_Top :unary
alias :visit_Arel_Nodes_UnqualifiedColumn :unary
@@ -75,7 +76,6 @@ module Arel
alias :visit_Arel_Nodes_NotEqual :binary
alias :visit_Arel_Nodes_NotIn :binary
alias :visit_Arel_Nodes_Or :binary
- alias :visit_Arel_Nodes_Ordering :binary
alias :visit_Arel_Nodes_OuterJoin :binary
alias :visit_Arel_Nodes_TableAlias :binary
alias :visit_Arel_Nodes_Values :binary
diff --git a/lib/arel/visitors/dot.rb b/lib/arel/visitors/dot.rb
index 92d05c7b67..8303279211 100644
--- a/lib/arel/visitors/dot.rb
+++ b/lib/arel/visitors/dot.rb
@@ -30,7 +30,6 @@ module Arel
private
def visit_Arel_Nodes_Ordering o
visit_edge o, "expr"
- visit_edge o, "direction"
end
def visit_Arel_Nodes_TableAlias o
diff --git a/lib/arel/visitors/to_sql.rb b/lib/arel/visitors/to_sql.rb
index 29e965bef8..933edc15f2 100644
--- a/lib/arel/visitors/to_sql.rb
+++ b/lib/arel/visitors/to_sql.rb
@@ -203,8 +203,12 @@ key on UpdateManager using UpdateManager#key=
"(#{visit o.expr})"
end
- def visit_Arel_Nodes_Ordering o
- "#{visit o.expr} #{o.descending? ? 'DESC' : 'ASC'}"
+ def visit_Arel_Nodes_Ascending o
+ "#{visit o.expr} ASC"
+ end
+
+ def visit_Arel_Nodes_Descending o
+ "#{visit o.expr} DESC"
end
def visit_Arel_Nodes_Group o
--
cgit v1.2.3
From 0c8723af70b8518c1a9ae43e650afb433e078470 Mon Sep 17 00:00:00 2001
From: Aaron Patterson <aaron.patterson@gmail.com>
Date: Mon, 27 Jun 2011 09:11:47 -0700
Subject: visitors can define their own cache strategy for dispatch. fixes #57
---
lib/arel/visitors/visitor.rb | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)
(limited to 'lib/arel/visitors')
diff --git a/lib/arel/visitors/visitor.rb b/lib/arel/visitors/visitor.rb
index c9cdf34adb..8f9dd929e1 100644
--- a/lib/arel/visitors/visitor.rb
+++ b/lib/arel/visitors/visitor.rb
@@ -11,15 +11,19 @@ module Arel
hash[klass] = "visit_#{(klass.name || '').gsub('::', '_')}"
end
+ def dispatch
+ DISPATCH
+ end
+
def visit object
- send DISPATCH[object.class], object
+ send dispatch[object.class], object
rescue NoMethodError => e
- raise e if respond_to?(DISPATCH[object.class], true)
+ raise e if respond_to?(dispatch[object.class], true)
superklass = object.class.ancestors.find { |klass|
- respond_to?(DISPATCH[klass], true)
+ respond_to?(dispatch[klass], true)
}
raise(TypeError, "Cannot visit #{object.class}") unless superklass
- DISPATCH[object.class] = DISPATCH[superklass]
+ dispatch[object.class] = dispatch[superklass]
retry
end
end
--
cgit v1.2.3