A.4.1: Does MySQL 5.5 support stored procedures and functions?
A.4.2: Where can I find documentation for MySQL stored procedures and stored functions?
A.4.3: Is there a discussion forum for MySQL stored procedures?
A.4.4: Where can I find the ANSI SQL 2003 specification for stored procedures?
A.4.5: How do you manage stored routines?
A.4.6: Is there a way to view all stored procedures and stored functions in a given database?
A.4.7: Where are stored procedures stored?
A.4.8: Is it possible to group stored procedures or stored functions into packages?
A.4.9: Can a stored procedure call another stored procedure?
A.4.10: Can a stored procedure call a trigger?
A.4.11: Can a stored procedure access tables?
A.4.12: Do stored procedures have a statement for raising application errors?
A.4.13: Do stored procedures provide exception handling?
A.4.14: Can MySQL 5.5 stored routines return result sets?
WITH RECOMPILE supported for stored
Is there a MySQL equivalent to using
mod_plsql as a gateway on Apache to talk
directly to a stored procedure in the database?
A.4.17: Can I pass an array as input to a stored procedure?
Can I pass a cursor as an
IN parameter to a
Can I return a cursor as an
from a stored procedure?
A.4.20: Can I print out a variable's value within a stored routine for debugging purposes?
A.4.21: Can I commit or roll back transactions inside a stored procedure?
A.4.22: Do MySQL 5.5 stored procedures and functions work with replication?
A.4.23: Are stored procedures and functions created on a master server replicated to a slave?
A.4.24: How are actions that take place inside stored procedures and functions replicated?
A.4.25: Are there special security requirements for using stored procedures and functions together with replication?
A.4.26: What limitations exist for replicating stored procedure and function actions?
A.4.27: Do the preceding limitations affect MySQL's ability to do point-in-time recovery?
A.4.28: What is being done to correct the aforementioned limitations?
Questions and Answers
Yes. MySQL 5.5 supports two types of stored routines—stored procedures and stored functions.
Yes. See http://forums.mysql.com/list.php?98.
Unfortunately, the official specifications are not freely available (ANSI makes them available for purchase). However, there are books—such as SQL-99 Complete, Really by Peter Gulutzan and Trudy Pelzer—which give a comprehensive overview of the standard, including coverage of stored procedures.
It is always good practice to use a clear naming scheme for your
stored routines. You can manage stored procedures with
[FUNCTION|PROCEDURE]. You can obtain information about
existing stored procedures using the
ROUTINES table in the
INFORMATION_SCHEMA database (see
Section 21.17, “The INFORMATION_SCHEMA ROUTINES Table”).
Yes. For a database named
this query on the
SELECT ROUTINE_TYPE, ROUTINE_NAME FROM INFORMATION_SCHEMA.ROUTINES WHERE ROUTINE_SCHEMA='
For more information, see Section 21.17, “The INFORMATION_SCHEMA ROUTINES Table”.
The body of a stored routine can be viewed using
SHOW CREATE FUNCTION (for a
stored function) or
PROCEDURE (for a stored procedure). See
Section 18.104.22.168, “SHOW CREATE PROCEDURE Syntax”, for more information.
proc table of the
mysql system database. However, you should
not access the tables in the system database directly. Instead,
SHOW CREATE FUNCTION to
obtain information about stored functions, and
SHOW CREATE PROCEDURE to obtain
information about stored procedures. See
Section 22.214.171.124, “SHOW CREATE PROCEDURE Syntax”, for more information
about these statements.
You can also query the
table in the
database—see Section 21.17, “The INFORMATION_SCHEMA ROUTINES Table”, for
information about this table.
No. This is not supported in MySQL 5.5.
A stored procedure can execute an SQL statement, such as an
UPDATE, that causes a trigger to
Yes. A stored procedure can access one or more tables as required.
Yes. MySQL 5.5 implements the SQL standard
statements. See Section 13.6.7, “Condition Handling”.
Stored procedures can, but stored functions
cannot. If you perform an ordinary
SELECT inside a stored procedure,
the result set is returned directly to the client. You need to
use the MySQL 4.1 (or above) client/server protocol for this to
work. This means that—for instance—in PHP, you need
to use the
mysqli extension rather than the
Not in MySQL 5.5.
There is no equivalent in MySQL 5.5.
Not in MySQL 5.5.
In MySQL 5.5, cursors are available inside stored procedures only.
In MySQL 5.5, cursors are available inside stored
procedures only. However, if you do not open a cursor on a
SELECT, the result will be sent
directly to the client. You can also
INTO variables. See Section 13.2.9, “SELECT Syntax”.
Yes, you can do this in a stored procedure,
but not in a stored function. If you perform an ordinary
SELECT inside a stored procedure,
the result set is returned directly to the client. You will need
to use the MySQL 4.1 (or above) client/server protocol for this
to work. This means that—for instance—in PHP, you
need to use the
mysqli extension rather than
Yes. However, you cannot perform transactional operations within a stored function.
Yes, standard actions carried out in stored procedures and functions are replicated from a master MySQL server to a slave server. There are a few limitations that are described in detail in Section 20.7, “Binary Logging of Stored Programs”.
Yes, creation of stored procedures and functions carried out
through normal DDL statements on a master server are replicated
to a slave, so the objects will exist on both servers.
for stored procedures and functions are also replicated.
MySQL records each DML event that occurs in a stored procedure and replicates those individual actions to a slave server. 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.
Yes. Because a slave server has authority to execute any statement read from a master'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, and therefore, random actions replicated
to a slave will not mirror those performed on a master.
Declaring stored functions to be
DETERMINISTIC or setting the
system variable to 0 will not allow random-valued operations to
In addition, time-based actions cannot be reproduced on a slave 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 master may be partially updated
from DML activity, but no updates are done to the slave because
of the errors that occurred. A workaround is for a function's
DML actions to be carried out with the
keyword so that updates on the master that cause errors are
ignored and updates that do not cause errors are replicated to
The same limitations that affect replication do affect point-in-time recovery.
You can choose either statement-based replication or row-based replication. The original replication implementation is based on statement-based binary logging. Row-based binary logging resolves the limitations mentioned earlier.
Mixed replication is also available (by
starting the server with
hybrid, “smart” form of replication
“knows” whether statement-level replication can
safely be used, or row-level replication is required.
For additional information, see Section 17.1.2, “Replication Formats”.