The result_names() predefines variables to be used in a result set to follow. The variables must be previously declared, from which the column data types are ascertained. This assigns the meta data but does not send any results. The result() function sends its parameters as a single row of results. These parameters should be compatible with those in the previous result_names(). The end_results() function can be used to separate multiple result sets. The result_names() can then be used to alter the structure of the next result set.
The result_names() call can be omitted if the application already knows what columns and their types are to be returned.
This examples demonstrates outputting multiple result sets from a stored procedure. This procedure can be entered using ISQL but ISQL does not support multiple result sets. To view the output you can use the the sample application odbctest or another application supporting multiple result sets. The RES procedure, below, returns two result sets, the first with two rows and the second with four rows. The result_names function gives each result column a type and title. This can be omitted if the application knows which columns to expect. The result function sends the actual result row. The end_result function indicates that a new result set will begin. These functions can be used inside loops or subprocedures, thus allowing one call to yield a variable number of result sets.
CREATE PROCEDURE RES (IN I INTEGER) { DECLARE STR, STR2 VARCHAR; RESULT_NAMES (I, STR); RESULT (I, 'FIRST'); RESULT (I + 1, 'SECOND'); RESULT_NAMES (I, STR, STR2); END_RESULT (); RESULT (I, 'FIRST'); RESULT (I + 1, 'SECOND'); RESULT (I + 2, 'THIRD', 'FF'); RESULT (I + 3, 'FOURTH', 'FF'); RETURN 1; }