SqlStatement.checkValidity

If cnc is not null, then checks that all the database objects referenced in the statement actually exist in the connection's database (for example the table being updated in a UPDATE statement must exist in the connection's database for the check to succeed). This method fills the stmt->validity_meta_struct attribute.

If cnc is null, then remove any information from a previous call to this method stored in stmt. In this case, the stmt->validity_meta_struct attribute is cleared.

Also note that some parts of stmt may be modified: for example leading and trailing spaces in aliases or objects names will be removed.