6 methods override Query::execute()

DeleteQuery::execute in includes/database/query.inc
Executes the DELETE query.
InsertQuery::execute in includes/database/query.inc
Executes the insert query.
MergeQuery::execute in includes/database/query.inc
Runs the query against the database.
SelectQuery::execute in includes/database/select.inc
Runs the query against the database.
TruncateQuery::execute in includes/database/query.inc
Executes the TRUNCATE query.
UpdateQuery::execute in includes/database/query.inc
Executes the UPDATE query.