Started from MySQL 5.0, Stored Procedure is supported in MySQL. 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. Here, the SQL command deletes a procedure which is already created.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. SQL Server, PostgreSQL, MySQL DROP PROCEDURE order_details We can delete stored procedures by using the DROP PROCEDURE command. Here, we've passed two parameters' values in a procedure. MySQL - Creating the stored procedure with cus_id and max_amount as parameters Where Customers.customer_id = cus_id AND Orders.amount < max_amount Where Customers.customer_id = AND Orders.amount < - Creating the stored procedure with cus_id and max_amount as parametersĬREATE PROCEDURE order_details (cus_id INT, max_amount INT) ON Customers.customer_id = Orders.customer_id SELECT Customers.customer_id, Customers.first_name, Orders.amount SQL Server - Creating the stored procedure with cus_id and max_amount as parametersĬREATE PROCEDURE order_details INT, INT AS PostgreSQL, MySQL - Calling the stored procedure with 'USA' as parameter valueĪ stored procedure can also take multiple parameters. Calling the same stored procedure again with another parameter value 'UK' SQL Server - Calling the stored procedure with 'USA' as parameter value Here, ctr is the parameter which we need to pass while calling the stored procedure. WHERE Country = CREATE PROCEDURE ctr_customers (ctr VARCHAR(50))ĬREATE PROCEDURE ctr_customers (ctr VARCHAR(50)) SQL Server CREATE PROCEDURE ctr_customers VARCHAR(50) AS So instead of writing the same code again, we can create a stored procedure and call it with different values. Notice that in the above two examples, everything is the same except the value to lookup in the country column. So we'll write our SQL statement as, SELECT *Īnd again if we want to fetch records where the value is UK in the country column, we'll write out SQL statement as, SELECT * Suppose we want to fetch records where the value is USA in the country column. We can pass our own data to stored procedures so the same SQL command works differently for different data. Following is the syntax to call the procedure. Now whenever we want to fetch all customers who live in the USA, we can simply call the procedure mentioned above. To invoke the stored procedure, the CALL statement is used. PostgreSQL CREATE PROCEDURE us_customers () After giving the Stored Procedure name, you can write a SQL statement between BEGIN and END. Here it will open a new window, where you will give a procedure name. SQL Server CREATE PROCEDURE us_customers AS Creating a Stored Procedure, you must apply the following steps: Select the database. We create stored procedures using the CREATE PROCEDURE command followed by SQL commands. They can accept parameters, and perform operations when we call them. Stored procedures are similar to functions in programming. We make stored procedures so that we can reuse statements that are used frequently. In SQL, stored procedure is a set of statement(s) that perform some defined actions.
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