(Quick Reference)
                executeUpdate
Purpose
Updates the database with 
DML-style operationsExamples
Account.executeUpdate("delete Book b where b.pages > 100")Account.executeUpdate("delete Book b where b.title like ?",
                      ['Groovy In Action'])Account.executeUpdate("delete Book b where b.author=?",
                      [Author.load(1)])Account.executeUpdate("update Book b set b.title='Groovy In Action'" +
                      "where b.title='GINA'")Account.executeUpdate("update Book b set b.title=:newTitle " +
                      "where b.title=:oldTitle",
                      [newTitle: 'Groovy In Action', oldTitle: 'GINA'])Description
GORM does not provide a 
deleteAll method as deleting data must be done with caution. To delete data you can use 
executeUpdate. The basic syntax is:
Book.executeUpdate(String query)
Book.executeUpdate(String query, List positionalParams)
Book.executeUpdate(String query, Map namedParams)
Parameters:
- query- An HQL query with DML-style operations
- positionalParams- A- Listof parameters for a positional parameterized HQL query
- namedParams- A- Mapof parameters for a named parameterized HQL query