Use the call statement to invoke a stored procedure.PostgreSQL is an open-source object-relational database system with 30+ years of active development in the industry.Use create procedure statement to define a new stored procedure.The following statement verifies the data in the accounts table after the transfer: SELECT * FROM accounts Code language: SQL (Structured Query Language) ( sql ) call transfer( 1, 2, 1000) Code language: SQL (Structured Query Language) ( sql ) To call a stored procedure, you use the CALL statement as follows: call stored_procedure_name(argument_list) Code language: SQL (Structured Query Language) ( sql )įor example, this statement invokes the transfer stored procedure to transfer $1,000 from Bob’s account to Alice’s account. adding the amount to the receiver's account update accountsĮnd $$ Code language: SQL (Structured Query Language) ( sql ) Calling a stored procedure create or replace procedure transfer(īegin - subtracting the amount from the sender's account update accounts The following example creates a stored procedure named transfer that transfers a specified amount of money from one account to another. The following statement shows the data from the accounts table: select * from accounts Code language: SQL (Structured Query Language) ( sql ) Values( 'Alice', 10000) Code language: SQL (Structured Query Language) ( sql ) We will use the following accounts table for the demonstration: drop table if exists accounts PostgreSQL CREATE PROCEDURE statement examples If you want to return a value from a stored procedure, you can use parameters with the inout mode. However, you can use the return statement without the expression to stop the stored procedure immediately: return Code language: SQL (Structured Query Language) ( sql ) You cannot use the return statement with a value inside a store procedure like this: return expression Code language: JavaScript ( javascript ) They cannot have the out mode.Ī stored procedure does not return a value. Parameters in stored procedures can have the in and inout modes. ![]() Finally, use the dollar-quoted string constant syntax to define the body of the stored procedure.Note that you can use other procedural languages for the stored procedure such as SQL, C, etc. Third, specify plpgsql as the procedural language for the stored procedure.A stored procedure can accept zero or more parameters. Second, define parameters for the stored procedure. ![]() First, specify the name of the stored procedure after the create procedure keywords.The following illustrates the basic syntax of the create procedure statement: create procedure procedure_name(parameter_list)ĭeclare - variable declaration begin - stored procedure body end $$ Code language: SQL (Structured Query Language) ( sql ) To define a new stored procedure, you use the create procedure statement. ![]() PostgreSQL 11 introduced stored procedures that support transactions. In other words, inside a user-defined function, you cannot start a transaction, and commit or rollback it. So far, you have learned how to define user-defined functions using the create function statement.Ī drawback of user-defined functions is that they cannot execute transactions. Introduction to PostgreSQL CREATE PROCEDURE statement Summary: in this tutorial, you will learn how to use the PostgreSQL CREATE PROCEDURE statement to create new stored procedures.
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