The mi_qual_funcid() accessor function
The mi_qual_funcid() function returns the routine identifier of a strategy function.
Syntax
mi_integer mi_qual_funcid(MI_AM_QUAL_DESC *qualDesc);
- qualDesc
- Points to the qualification descriptor.
Usage
To execute a registered UDR or an internal function with DataBlade API Fastpath facility, the access method needs a valid routine identifier. The mi_qual_funcid() function provides a routine identifier, if available, for the strategy function.
If mi_qual_funcid() returns a positive number, the routine identifier exists in the sysprocedures system catalog table, and the database server can execute the function. A negative return value from the mi_qual_funcid() function can indicate a valid function if the database server loads an internal function in shared memory but does not describe the function in sysprocedures.
A negative return value might indicate that the SQL WHERE clause specified an invalid function.
Return values
A positive integer is the routine identifier by which the database server recognizes a function.
A negative return value indicates that the sysprocedures system catalog table does not have a routine identifier for the function.
Related topics
- The function descriptor (MI_FUNC_DESC data structure) and its accessor functions
- Fastpath function execution, including DataBlade API functions mi_func_desc_by_typeid() and mi_routine_exec()