Now we have created a new stored procedure, but we also need to know however to invoke it in program or in command line of MySQL. We can analysis more details of each part later. The body part of the stored procedure started with between BEGIN and END block. After the CREATE PROCEDURE statement you can specify the name of stored procedure, in this case it is GetAllProducts. In order to create a new stored procedure you use CREATE PROCEDURE statement. The last command changes the delimiter back to the standard one (semicolon). After the END keyword we use delimiter // to show the end of the stored procedure. DELIMITER statement is used to change the standard delimiter (semicolon) to another, in this case the delimiter is changed to //, so you can have multiple SQL statements inside stored procedure which can separate by the semicolon. This command is not related to the stored procedure. The first command you see is DELIMITER //. MULTIPLE SELECTS IN STORED PROCEDURE MYSQL JDBC CODEFirst let’s take a look at the stored procedure source code bellow: It retrieves all products from products table. The first stored procedure is very simple. In this tutorial, you will write the first simple stored procedure and invoke it from command line of MySQL. Getting Started with MySQL Stored Procedures MULTIPLE SELECTS IN STORED PROCEDURE MYSQL JDBC HOW TOThe following tutorial we will guide you how to leverage stored procedure in your database programming task with a couple of practical examples. So when developing application you should balance between them to choose whether to use stored procedure or not. Stored procedure has it own advantages and disadvantages as mentioned above. This introduced the problem in both application development and maintain phrase. Writing and maintain stored procedure usually required specialized skill set that not all developers possess. There are some workarounds on this problem but it still not good enough to do so. You cannot debug stored procedure in almost RDMBSs and in MySQL also. Stored procedure only contains declarative SQL so it is very difficult to write a procedure with complexity of business like other languages in application layer such as Java, C#, C++… Instead of being focused on the storing and retrieving data, you could be asking the database server to perform a number of logical operations or a complex of business logic which is not the role of it. Stored procedure make the database server high load in both memory for and processors. Database administrator can grant the right to application which to access which stored procedures in database catalog without granting any permission on the underlying database table.Beside those advantages, stored procedure still has its own disadvantages which are bellow Stored procedure exposes the database interface to all applications so developer doesn’t have to program the functions which are already supported in stored procedure in all programs. Stored procedure is reusable and transparent to any application which wants to use it. Stored procedure reduced the traffic between application and database server because instead of sending multiple uncompiled long SQL commands statement, application only has to send the stored procedure name and get the result back. It runs faster than uncompiled SQL commands which are sent from application Once created, stored procedure is compiled and stored in the database catalog. Stored procedure increases performance of application. MULTIPLE SELECTS IN STORED PROCEDURE MYSQL JDBC SERIESTherefore before start the tutorial series about Stored procedure, it is required that you have MySQL version > 5.x installed in your computer. MySQL certainly is the most open source RDBMS which is widely used by both community and enterprise but during the first decade of its existence, it did not support stored procedure, trigger, event…Since MySQL version 5.0, those features has been added to MySQL database engine to allow MySQL more flexible and powerful. Check your version of MySQL before using recursive stored procedure Almost RDMBS supports recursive stored procedure but MySQL does not support it well. A stored procedure, by definition, is a segment of declarative SQL code which is stored in the database catalog and can be invoked later by a program, a trigger or even a stored procedure.Ī stored procedure, which calls itself, is recursive stored procedure.
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