diff options
7 files changed, 43 insertions, 0 deletions
diff --git a/activerecord/CHANGELOG b/activerecord/CHANGELOG index d80109b16d..668df3698f 100644 --- a/activerecord/CHANGELOG +++ b/activerecord/CHANGELOG @@ -1,5 +1,7 @@ *SVN* +* Add AbstractAdapter#table_alias_for to create table aliases according to the rules of the current adapter. [Rick] + * Provide access to the underlying database connection through Adapter#raw_connection. Enables the use of db-specific methods without complicating the adapters. #2090 [Koz] * Remove broken attempts at handling columns with a default of 'now()' in the postgresql adapter. #2257 [Koz] diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb index 76967c0fe0..d0b8a1ba1c 100644 --- a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb +++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb @@ -8,6 +8,20 @@ module ActiveRecord {} end + # This is the maximum length a table alias can be + def table_alias_length + 255 + end + + # Truncates a table alias according to the limits of the current adapter. + def table_alias_for(table_name, index = 1) + if index > 1 + "#{table_name[0..table_alias_length-3]}_#{index}" + else + table_name[0..table_alias_length-1] + end + end + # def tables(name = nil) end # Returns an array of indexes for the given table. diff --git a/activerecord/lib/active_record/connection_adapters/db2_adapter.rb b/activerecord/lib/active_record/connection_adapters/db2_adapter.rb index 06c13c39ad..9819c5a92a 100644 --- a/activerecord/lib/active_record/connection_adapters/db2_adapter.rb +++ b/activerecord/lib/active_record/connection_adapters/db2_adapter.rb @@ -188,6 +188,10 @@ begin def reconnect! end + def table_alias_length + 128 + end + private def with_statement diff --git a/activerecord/lib/active_record/connection_adapters/oracle_adapter.rb b/activerecord/lib/active_record/connection_adapters/oracle_adapter.rb index 3291fac455..c34b3596df 100644 --- a/activerecord/lib/active_record/connection_adapters/oracle_adapter.rb +++ b/activerecord/lib/active_record/connection_adapters/oracle_adapter.rb @@ -191,6 +191,9 @@ begin } end + def table_alias_length + 30 + end # QUOTING ================================================== # diff --git a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb index 354df9a42e..53f47b2ad6 100644 --- a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb +++ b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb @@ -101,6 +101,9 @@ module ActiveRecord true end + def table_alias_length + 63 + end # QUOTING ================================================== diff --git a/activerecord/lib/active_record/connection_adapters/sybase_adapter.rb b/activerecord/lib/active_record/connection_adapters/sybase_adapter.rb index 67d1c368eb..75a0b4ed18 100644 --- a/activerecord/lib/active_record/connection_adapters/sybase_adapter.rb +++ b/activerecord/lib/active_record/connection_adapters/sybase_adapter.rb @@ -150,6 +150,10 @@ module ActiveRecord # connect! # Not yet implemented end + def table_alias_length + 30 + end + # Check for a limit statement and parse out the limit and # offset if specified. Remove the limit from the sql statement # and call select. diff --git a/activerecord/test/adapter_test.rb b/activerecord/test/adapter_test.rb index af76ebfc9a..2c98045cee 100644 --- a/activerecord/test/adapter_test.rb +++ b/activerecord/test/adapter_test.rb @@ -46,6 +46,19 @@ class AdapterTest < Test::Unit::TestCase end end + def test_table_alias + old = @connection.table_alias_length + def @connection.table_alias_length() 10; end + + assert_equal 'posts', @connection.table_alias_for('posts') + assert_equal 'posts', @connection.table_alias_for('posts', 1) + assert_equal 'posts_2', @connection.table_alias_for('posts', 2) + assert_equal 'posts_comm', @connection.table_alias_for('posts_comments') + assert_equal 'posts_co_2', @connection.table_alias_for('posts_comments', 2) + + def @connection.table_alias_length() old; end + end + # test resetting sequences in odd tables in postgreSQL if ActiveRecord::Base.connection.respond_to?(:reset_pk_sequence!) require 'fixtures/movie' |