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February 25, 2010 10:14
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From 8812b05e24aeb70099e50bb2716b647555902365 Mon Sep 17 00:00:00 2001 | |
From: Praveen Devarao <praveen@falcon> | |
Date: Thu, 25 Feb 2010 12:49:19 +0530 | |
Subject: [PATCH] Moved adding of limit on deletion and adding of limit on update conditions to GenericCompiler, to provide flexibility to handle db specifics | |
--- | |
lib/arel/engines/sql/compilers/ibm_db_compiler.rb | 62 +++++++++++++++++++++ | |
lib/arel/engines/sql/relations/compiler.rb | 7 ++- | |
lib/arel/engines/sql/relations/writes.rb | 6 +- | |
3 files changed, 70 insertions(+), 5 deletions(-) | |
create mode 100644 lib/arel/engines/sql/compilers/ibm_db_compiler.rb | |
diff --git a/lib/arel/engines/sql/compilers/ibm_db_compiler.rb b/lib/arel/engines/sql/compilers/ibm_db_compiler.rb | |
new file mode 100644 | |
index 0000000..e6be73d | |
--- /dev/null | |
+++ b/lib/arel/engines/sql/compilers/ibm_db_compiler.rb | |
@@ -0,0 +1,62 @@ | |
+# +-----------------------------------------------------------------------+ | |
+# | | | |
+# | Copyright (c) 2010 IBM Corporation | | |
+# | | | |
+# | Permission is hereby granted, free of charge, to any person obtaining | | |
+# | a copy of this software and associated documentation files (the | | |
+# | "Software"), to deal in the Software without restriction, including | | |
+# | without limitation the rights to use, copy, modify, merge, publish, | | |
+# | distribute, sublicense, and/or sell copies of the Software, and to | | |
+# | permit persons to whom the Software is furnished to do so, subject to | | |
+# | the following conditions: | | |
+# | | | |
+# | The above copyright notice and this permission notice shall be | | |
+# | included in all copies or substantial portions of the Software. | | |
+# | | | |
+# | THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, | | |
+# | EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF | | |
+# | MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.| | |
+# | IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR | | |
+# | ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION | | |
+# | OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION | | |
+# | WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. | | |
+# | | | |
+# +-----------------------------------------------------------------------+ | |
+ | |
+# | |
+# Author: Praveen Devarao <praveendrl@in.ibm.com> | |
+# | |
+ | |
+module Arel | |
+ module SqlCompiler | |
+ class IBM_DBCompiler < GenericCompiler | |
+ | |
+ def select_sql | |
+ query = build_query \ | |
+ "SELECT #{select_clauses.join(', ')}", | |
+ "FROM #{from_clauses}", | |
+ (joins(self) unless joins(self).blank? ), | |
+ ("WHERE #{where_clauses.join(" AND ")}" unless wheres.blank? ), | |
+ ("GROUP BY #{group_clauses.join(', ')}" unless groupings.blank? ), | |
+ ("HAVING #{having_clauses.join(', ')}" unless havings.blank? ), | |
+ ("ORDER BY #{order_clauses.join(', ')}" unless orders.blank? ) | |
+ engine.add_limit_offset!(query,{:limit=>taken,:offset=>skipped}) unless taken.blank? | |
+ query << "#{locked}" unless locked.blank? | |
+ query | |
+ end | |
+ | |
+ def limited_update_conditions(conditions, taken) | |
+ quoted_primary_key = engine.quote_table_name(primary_key) | |
+ update_conditions = "WHERE #{quoted_primary_key} IN (SELECT #{quoted_primary_key} FROM #{engine.connection.quote_table_name table.name} #{conditions} " #Note: - ')' not added, limit segment is to be appended | |
+ engine.add_limit_offset!(update_conditions,{:limit=>taken,:offset=>nil}) | |
+ update_conditions << ")" # Close the sql segment | |
+ update_conditions | |
+ end | |
+ | |
+ def add_limit_on_delete(taken) | |
+ "" # Limiting the number of rows to be deleted is not supported by IBM_DB | |
+ end | |
+ | |
+ end | |
+ end | |
+end | |
diff --git a/lib/arel/engines/sql/relations/compiler.rb b/lib/arel/engines/sql/relations/compiler.rb | |
index c974e43..597ed88 100644 | |
--- a/lib/arel/engines/sql/relations/compiler.rb | |
+++ b/lib/arel/engines/sql/relations/compiler.rb | |
@@ -21,11 +21,16 @@ module Arel | |
("#{locked}" unless locked.blank?) | |
end | |
- def limited_update_conditions(conditions) | |
+ def limited_update_conditions(conditions, taken) | |
+ conditions << " LIMIT #{taken}" | |
quoted_primary_key = engine.quote_table_name(primary_key) | |
"WHERE #{quoted_primary_key} IN (SELECT #{quoted_primary_key} FROM #{engine.connection.quote_table_name table.name} #{conditions})" | |
end | |
+ def add_limit_on_delete(taken) | |
+ "LIMIT #{taken}" | |
+ end | |
+ | |
def supports_insert_with_returning? | |
false | |
end | |
diff --git a/lib/arel/engines/sql/relations/writes.rb b/lib/arel/engines/sql/relations/writes.rb | |
index 0a6250a..54eaee9 100644 | |
--- a/lib/arel/engines/sql/relations/writes.rb | |
+++ b/lib/arel/engines/sql/relations/writes.rb | |
@@ -5,7 +5,7 @@ module Arel | |
"DELETE", | |
"FROM #{table_sql}", | |
("WHERE #{wheres.collect(&:to_sql).join(' AND ')}" unless wheres.blank? ), | |
- ("LIMIT #{taken}" unless taken.blank? ) | |
+ (compiler.add_limit_on_delete(taken) unless taken.blank? ) | |
end | |
end | |
@@ -68,9 +68,7 @@ module Arel | |
conditions << " ORDER BY #{order_clauses.join(', ')}" unless orders.blank? | |
unless taken.blank? | |
- conditions << " LIMIT #{taken}" | |
- | |
- conditions = compiler.limited_update_conditions(conditions) | |
+ conditions = compiler.limited_update_conditions(conditions,taken) | |
end | |
conditions | |
-- | |
1.6.0 | |
From 860ad2230ce658432bf62578c7d65285994e1cfa Mon Sep 17 00:00:00 2001 | |
From: Praveen Devarao <praveen@falcon> | |
Date: Thu, 25 Feb 2010 14:35:16 +0530 | |
Subject: [PATCH] raise an error if limit for deletion is specified while using IBM_DB | |
--- | |
lib/arel/engines/sql/compilers/ibm_db_compiler.rb | 2 +- | |
1 files changed, 1 insertions(+), 1 deletions(-) | |
diff --git a/lib/arel/engines/sql/compilers/ibm_db_compiler.rb b/lib/arel/engines/sql/compilers/ibm_db_compiler.rb | |
index e6be73d..e15e783 100644 | |
--- a/lib/arel/engines/sql/compilers/ibm_db_compiler.rb | |
+++ b/lib/arel/engines/sql/compilers/ibm_db_compiler.rb | |
@@ -54,7 +54,7 @@ module Arel | |
end | |
def add_limit_on_delete(taken) | |
- "" # Limiting the number of rows to be deleted is not supported by IBM_DB | |
+ raise "IBM_DB does not support limit on deletion" # Limiting the number of rows to be deleted is not supported by IBM_DB | |
end | |
end | |
-- | |
1.6.0 | |
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