IF EXISTS is the optional statement that can be used to avoid raising the error when no stored procedure with name_of_SP exists in your database and you are trying to delete it. If we want to delete the stored procedure, then we can drop it using the following syntax: DROP procedure name_of_SP Executing the above calling statement gives the following output: The stored procedure call mentioned above will return the list of all label numbers whose last transaction occurred on the 1st of December 2012. In our above example, we can call the GetLabelsOfLastTransDate stored procedure simply by using the following call statement – CALL GetLabelsOfLastTransDate ('') Ĭalling the stored procedure mentioned above will result in the retrieval of the list of all label numbers whose last transaction occurred on the 1st of December 2012. Our stored procedure will be as follows: DELIMITER $$ĬREATE PROCEDURE GetLabelsOfLastTransDate(IN last_trans_date DATE)ĭELIMITER Calling the Stored Procedure in MySQLīelow is the syntax for calling or executing the stored procedure: CALL name_of_SP (value of parameters accepted by stored procedure) Now, let’s create a stored procedure that returns the label numbers for which the last transaction date is passed as a parameter to the GetLabelsOfLastTransDate procedure. Hence 30 rows are present in the last_tran_date table. Let us confirm all the inserted values using the SELECT query: SELECT * FROM 'last_tran_date' 'LabelNo' int(11) NOT NULL DEFAULT '0' COMMENT 'Generated Label No',Īnd add some of the values using INSERT statement like the following: INSERT INTO 'last_tran_date' ('itemCode', 'LabelNo', 'LastTranDate') VALUES('87','8529816','') Ģ. 'itemCode' int(11) NOT NULL COMMENT 'ItemCode From Item Master', Still, before that, I will create a sample table named last_tran_date that will store the date of the last transaction on the particular object along with its item code and label number using the following query: CREATE TABLE 'last_tran_date' ( Let us create one simple stored procedure. Example to Implement MySQL Stored Procedureīelow are some examples of MySQL Stored Procedures:ġ. You can also include calls to other stored procedures within this section of the stored procedure. Execution part of the stored procedure: We can write our program or code in this section of the stored procedure that can contain conditional, looping statements, initializing and assigning the value of variables, and preparing and executing the database queries. Declaration part of the stored procedure: We can declare the local variables if we want any in this part of the stored procedure.ĥ. BEGIN and END: BEGIN keyword marks the beginning of the stored procedure, while END marks the completion of the stored procedure in MYSQL.Ĥ. IN OUT: These parameters are assigned the values while calling the stored procedure, and the value can be modified or overwritten inside the stored procedure and referenced and used by the stored procedure.ģ.OUT:You can assign values to these parameters and override them in the stored procedure, but you cannot reference them directly.They cannot be modified or overwritten within the stored procedure. IN: You assign values to these parameters when calling the stored procedure, and the stored procedure references and utilizes these values.These parameters can belong to either of the three types: A stored procedure can contain none, one, or more than one parameter. NameOfParameter: We can pass the optional parameters to the stored procedures that must be declared while creating it in the () brackets. name_of_SP: The stored procedure’s name needs to be created in MySQL.Ģ. Started from MySQL 5.0, Stored Procedure is supported in MySQL.Let us learn the syntax of creating the stored procedure: CREATE PROCEDURE name_of_SP )]ġ. You can grant access to a procedure for an user even if that user doesn’t have direct access to the tables. It limits direct access to tables via defined roles in the database.It’s one of the best practices to prevent SQL Injection. One line statement calling the stored procedure instead of multiple lines of the individual query will be sent over the network so it reduces the traffic between the client and the server. Compile it once and reuse it anytime you want. Stored procedures are compiled once and stored in an executable form, thus calling it would be quick and efficient. Why is using stored procedure recommended? The next time you need it, just call by its name and the set of queries will be executed easier, faster, and more secure. A stored procedure is a batch of SQL queries that can be stored on the server.Īfter being issued and executed for the first time, stored procedure will be optimized and saved on the server.
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