Memory used for UNDO_BUFFER_SIZE  comes from the global pool whose size is determined by the value of the SharedGlobalMemory  data node configuration parameter. This includes any default value implied for this option by the setting of the InitialLogFileGroup  data node configuration parameter. 

ALTER LOGFILE GROUP  is useful only with Disk Data storage for NDB Cluster. For more information, see Section 23.5.10, “NDB Cluster Disk Data Tables” . 

## 13.1.7 ALTER PROCEDURE Statement 

ALTER PROCEDURE proc_name  [ characteristic  ...] characteristic : { COMMENT ’ string ’ | LANGUAGE SQL | { CONTAINS SQL | NO SQL | READS SQL DATA | MODIFIES SQL DATA } | SQL SECURITY { DEFINER | INVOKER } } 

This statement can be used to change the characteristics of a stored procedure. More than one change may be specified in an ALTER PROCEDURE  statement. However, you cannot change the parameters or body of a stored procedure using this statement; to make such changes, you must drop and re-create the procedure using DROP PROCEDURE  and CREATE PROCEDURE . 

You must have the ALTER ROUTINE  privilege for the procedure. By default, that privilege is granted automatically to the procedure creator. This behavior can be changed by disabling the automatic_sp_privileges  system variable. See Section 25.2.2, “Stored Routines and MySQL Privileges” . 

## 13.1.8 ALTER SERVER Statement 

ALTER SERVER server_name OPTIONS ( option  [, option ] ...) 

Alters the server information for server_name , adjusting any of the options permitted in the CREATE SERVER  statement. The corresponding fields in the mysql.servers  table are updated accordingly. This statement requires the SUPER  privilege. 

For example, to update the USER  option: 

ALTER SERVER s OPTIONS (USER ’sally’); 

ALTER SERVER  causes an implicit commit. See Section 13.3.3, “Statements That Cause an Implicit Commit” . 

ALTER SERVER  is not written to the binary log, regardless of the logging format that is in use. 

## 13.1.9 ALTER TABLE Statement 

ALTER TABLE tbl_name [ alter_option  [, alter_option ] ...] [ partition_options ] alter_option : { table_options | ADD [COLUMN] col_name column_definition [FIRST | AFTER col_name ] | ADD [COLUMN] ( col_name column_definition ,...) | ADD {INDEX | KEY} [ index_name ] [ index_type ] ( key_part ,...) [ index_option ] ... | ADD {FULLTEXT | SPATIAL} [INDEX | KEY] [ index_name ] ( key_part ,...) [ index_option ] ... | ADD [CONSTRAINT [ symbol ]] PRIMARY KEY 

