A stored procedure is a pre-compiled program that can be called multiple times. In Oracle, stored procedures can have input parameters, output parameters, or both. In this article, we will delve into how to use output parameters in stored procedures.
Steps:
In order to use output parameters in a stored procedure, we need to declare one in the parameter list of the stored procedure Output parameters. Here is an example:
CREATE OR REPLACE PROCEDURE my_proc (IN_PARAM1 IN NUMBER, OUT_PARAM1 OUT NUMBER) IS
BEGIN
-- Stored procedure body
END;
Here we define an output parameter named OUT_PARAM1, which will be used in the stored procedure.
In the stored procedure body, we need to set the value of the output parameter. Here is an example:
CREATE OR REPLACE PROCEDURE my_proc (IN_PARAM1 IN NUMBER, OUT_PARAM1 OUT NUMBER) IS
BEGIN
SELECT COUNT(*) INTO OUT_PARAM1 FROM my_table WHERE column1 = IN_PARAM1;
END;
Here we execute a SELECT query and store the results in OUT_PARAM1. Note that we used the INTO keyword to specify where the value should be stored.
When calling stored procedures, we need to pass input parameters and receive the values of output parameters. Here is an example:
DECLARE
my_output_param NUMBER;
BEGIN
my_proc(1, my_output_param);
DBMS_OUTPUT.PUT_LINE ('My output parameter value is: ' || my_output_param);
END;
Here we call the my_proc stored procedure and pass 1 as the input parameter. The value of the output parameter is stored in the my_output_param variable and printed to the console.
Summary:
Through this article, we learned how to use output parameters in stored procedures in Oracle. This is a very useful technique that allows us to use stored procedures more efficiently. If you have trouble writing a stored procedure, refer to this article and always remember to declare your output parameters in the parameter list of the stored procedure.
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