Handling Scalar Functions

The OpenAccess SDK SQL engine will push down the scalar functions used in the search expressions. The IP needs to support all standard scalar functions (such as UPPER, LOWER, CONCAT) and any custom scalar functions used in the search expression of the query.

If the IP expects some custom scalar functions to be used only in search expressions, the custom scalar function implementation is not required to be registered with the OpenAccess SDK SQL engine. The OpenAccess SDK SQL engine will report an error during execution only if these non-registered custom functions are used in the select-list.

Example: If LEN() is a non-registered scalar function:

Supported Query: SELECT * FROM emp WHERE LEN(ename)>0;

Unsupported Query: SELECT LEN(ename) FROM emp;