This method will not be supported indefinitely. There are, how- ever, subtleties which must be addressed in order for a mixed query language application to perform properly. The purpose of this document is to discuss these subtleties.
Programmers often combine many callable routines into one com- pilable file.
If this method is used one must insure that no constructs from QUEL are intermixed with SQL constructs within the entire file. Those functions of a given query language will have to combined into a separate module and compiled separately. Invoking a SQL database procedure while in a QUEL-based transaction is not allowed. In order to invoke a SQL database procedure one must either already be within a SQL initiated MQT or end the current QUEL initiated MQT prior to invoking the SQL database procedure. The error number provided to the error handler will contain the proper SQL error number.