Cursors Cursors — learn how to use cursors to process row by row in a result set. Section 6. Stored Functions Creating a stored function — show you how to use the create stored functions in the database. Section 7. Stored Program Security Stored object access control — learn how to control the security of the stored objects.
Up Next. In MySQL 8. Can I print out a variable's value within a stored routine for debugging purposes? Yes, you can do this in a stored procedure , but not in a stored function. You must use the MySQL 4. However, you cannot perform transactional operations within a stored function.
Yes, standard actions carried out in stored procedures and functions are replicated from a replication source server to a replica.
There are a few limitations that are described in detail in Section Are stored procedures and functions created on a replication source server replicated to a replica? Yes, creation of stored procedures and functions carried out through normal DDL statements on a replication source server are replicated to a replica, so that the objects exist on both servers. How are actions that take place inside stored procedures and functions replicated?
The actual calls made to execute stored procedures are not replicated. Stored functions that change data are logged as function invocations, not as the DML events that occur inside each function. Are there special security requirements for using stored procedures and functions together with replication?
Because a replica has authority to execute any statement read from a source's binary log, special security constraints exist for using stored functions with replication. If replication or binary logging in general for the purpose of point-in-time recovery is active, then MySQL DBAs have two security options open to them:.
Nondeterministic random or time-based actions embedded in stored procedures may not replicate properly. By their very nature, randomly produced results are not predictable and cannot be exactly reproduced; therefore, random actions replicated to a replica do not mirror those performed on a source. In addition, time-based actions cannot be reproduced on a replica because the timing of such actions in a stored procedure is not reproducible through the binary log used for replication. It records only DML events and does not factor in timing constraints.
Finally, nontransactional tables for which errors occur during large DML actions such as bulk inserts may experience replication issues in that a source may be partially updated from DML activity, but no updates are done to the replica because of the errors that occurred.
A workaround is for a function's DML actions to be carried out with the IGNORE keyword so that updates on the source that cause errors are ignored and updates that do not cause errors are replicated to the replica. In this article, we are going to learn about the stored procedures in MySQL.
In this article, I am covering the basics of the stored procedure that includes the following. The stored procedure can also execute another stored procedure or a function that modularizes the code. Let us create a basic stored procedure. For demonstration, I am using the sakila database. Suppose you want to populate the list of films.
The code of the procedure is the following:. We can use the MySQL workbench wizard to create a stored procedure. Suppose you want to get the list of the customer from the sakila database. In the New procedure window, a create template has been created. In the code block, enter the following query.
Click on Apply. A dialog box, Apply script to database opens. On the Review the script screen, you can view the code of the stored procedure.
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