When we include a SQL statement that does not return a result setsuch as an UPDATE, INSERT, or SET statementwithin a stored program, it will execute exactly as it would if it were executed in some other context (such as if it were called from PHP or issued from the MySQL command line).
SQL statements within stored programs follow the same syntax as they would outside of the stored program. The SQL statements have full access to any stored program variables, which can be used wherever a literal or expression would normally be provided to the SQL.
You can use all the major categories of SQL statements inside stored programs. DML, DDL, and utility statements can be used without restriction.
Example 5-1 uses a combination of DDL and DML to create and manipulate the data in a table.
Example 5-1. Embedding non-SELECT statements in stored programs
CREATE PROCEDURE simple_sqls( ) BEGIN DECLARE i INT DEFAULT 1; /* Example of a utility statement */ SET autocommit=0; /* Example of DDL statements */ DROP TABLE IF EXISTS test_table ; CREATE TABLE test_table (id INT PRIMARY KEY, some_data VARCHAR(30)) ENGINE=innodb; /* Example of an INSERT using a procedure variable */ WHILE (i<=10) DO INSERT INTO TEST_TABLE VALUES(i,CONCAT("record ",i)); SET i=i+1; END WHILE; /* Example of an UPDATE using procedure variables*/ SET i=5; UPDATE test_table SET some_data=CONCAT("I updated row ",i) WHERE id=i; /* DELETE with a procedure variable */ DELETE FROM test_table WHERE id>i; END;
Part I: Stored Programming Fundamentals
Introduction to MySQL Stored Programs
MySQL Stored Programming Tutorial
Blocks, Conditional Statements, and Iterative Programming
Using SQL in Stored Programming
Part II: Stored Program Construction
Creating and Maintaining Stored Programs
MySQL Built-in Functions
Part III: Using MySQL Stored Programs in Applications
Using MySQL Stored Programs in Applications
Using MySQL Stored Programs with PHP
Using MySQL Stored Programs with Java
Using MySQL Stored Programs with Perl
Using MySQL Stored Programs with Python
Using MySQL Stored Programs with .NET
Part IV: Optimizing Stored Programs
Stored Program Security
Tuning Stored Programs and Their SQL
Basic SQL Tuning
Advanced SQL Tuning
Optimizing Stored Program Code
Best Practices in MySQL Stored Program Development