Micro Focus Studio Enterprise Edition for Windows > Programming > Data Access > Database Access > OpenESQL > Programming for OpenESQL > Working With OpenESQL Stored Procedures and Result Sets

Working With OpenESQL Stored Procedures and Result Sets

An OpenESQL stored procedure can:

Accept input parameters
Return output parameters
Accept and return input/output parameters
Use positional or keyword parameters
Return one or more forward only read only result sets
Be called with parameter arrays

Note: The features provided by different database vendors vary considerably, and any given vendor might offer only a subset of the features listed above. For this reason, stored procedure calls are much less portable between data sources than other OpenESQL statements.

Calling a Stored Procedure that Returns No Result Sets

To call a stored procedure that returns no result sets, use the CALL embedded SQL statement, or the EXECSP embedded SQL statement if you want to ensure backward compatibility with the Micro Focus Embedded SQL Toolkit for Microsoft SQL Server. For complete details on using these statements, see the CALL and EXECSP topics.

Calling a Stored Procedure that Returns One or More Result Sets

If a stored procedure returns one or more result sets, you must first declare it using the DECLARE CURSOR statement. For example:

         EXEC SQL 
                DECLARE cursorName CURSOR FOR storedProcedureCallStatement
         END-EXEC

You then call the stored procedure just as you would any other type of cursor using the OPEN statement to open the cursor, followed by the FETCH statement to fetch result set rows.

If your stored procedure is coded to return more than one result set, and your FETCH statement returns an SQLCODE of 100 (signifying the end of the current result set), you can issue the GET NEXT RESULT SET statement to fetch the next result set as follows:

          EXEC SQL
                 GET NEXT RESULT SET FOR cursorName
          END-EXEC

If your GET NEXT RESULT SET statement returns an SQLCODE of 0, another result set is available, and you can issue another GET NEXT RESULT SET to retrieve it. However, if GET NEXT RESULT SET returns an SQLCODE of 100, no additional result sets are available.

Using Array Parameters

ODBC parameters differ from Oracle array parameters. The effect of using a parameter array is the same as repeating the statement for each element of the array. On a stored procedure call, if one parameter is passed as an array, then all parameters must be arrays with the same number of elements. The stored procedure "sees" one call for each "row" of parameters. The number of rows passed can be limited to less than the full array size by preceding the call with the following phrase:

FOR :hvar

Where :hvar is an integer host variable containing a count of the number of rows to be passed.