Module | ActiveRecord::ConnectionAdapters::DatabaseStatements |
In: |
lib/active_record/connection_adapters/abstract/database_statements.rb
|
Appends LIMIT and OFFSET options to a SQL statement. This method modifies the sql parameter.
add_limit_offset!('SELECT * FROM suppliers', {:limit => 10, :offset => 50})
generates
SELECT * FROM suppliers LIMIT 10 OFFSET 50
Appends a locking clause to a SQL statement. *Modifies the sql parameter*.
# SELECT * FROM suppliers FOR UPDATE add_lock! 'SELECT * FROM suppliers', :lock => true add_lock! 'SELECT * FROM suppliers', :lock => ' FOR UPDATE'
Rolls back the transaction (and turns on auto-committing). Must be done if the transaction block raises an exception or returns false.
Returns an array of the values of the first column in a select:
select_values("SELECT id FROM companies LIMIT 3") => [1,2,3]
Wrap a block in a transaction. Returns result of block.