The privileges granted to a MySQL account determine which operations the account can perform. MySQL privileges differ in the contexts in which they apply and at different levels of operation:
Administrative privileges enable users to manage operation of the MySQL server. These privileges are global because they are not specific to a particular database.
Database privileges apply to a database and to all objects within it. These privileges can be granted for specific databases, or globally so that they apply to all databases.
Privileges for database objects such as tables, indexes, views, and stored routines can be granted for specific objects within a database, for all objects of a given type within a database (for example, all tables in a database), or globally for all objects of a given type in all databases).
Information about account privileges is stored in the
user, db,
tables_priv, columns_priv,
and procs_priv tables in the
mysql system database (see
Section 6.2.2, “Grant Tables”). The MySQL server reads the
contents of these tables into memory when it starts and reloads
them under the circumstances indicated in
Section 6.2.6, “When Privilege Changes Take Effect”. Access-control decisions are
based on the in-memory copies of the grant tables.
Some MySQL releases introduce changes to the structure of the grant tables to add new privileges or features. To make sure that you can take advantage of any new capabilities, update your grant tables to have the current structure whenever you upgrade MySQL. See Section 4.4.7, “mysql_upgrade — Check and Upgrade MySQL Tables”.
The following table shows the privilege names used in
GRANT and
REVOKE statements, along with the
column name associated with each privilege in the grant tables and
the context in which the privilege applies.
Table 6.2 Permissible Privileges for GRANT and REVOKE
| Privilege | Column | Context |
|---|---|---|
ALL [PRIVILEGES] | Synonym for “all privileges” | Server administration |
ALTER | Alter_priv | Tables |
ALTER ROUTINE | Alter_routine_priv | Stored routines |
CREATE | Create_priv | Databases, tables, or indexes |
CREATE ROUTINE | Create_routine_priv | Stored routines |
CREATE TABLESPACE | Create_tablespace_priv | Server administration |
CREATE TEMPORARY TABLES | Create_tmp_table_priv | Tables |
CREATE USER | Create_user_priv | Server administration |
CREATE VIEW | Create_view_priv | Views |
DELETE | Delete_priv | Tables |
DROP | Drop_priv | Databases, tables, or views |
EVENT | Event_priv | Databases |
EXECUTE | Execute_priv | Stored routines |
FILE | File_priv | File access on server host |
GRANT OPTION | Grant_priv | Databases, tables, or stored routines |
INDEX | Index_priv | Tables |
INSERT | Insert_priv | Tables or columns |
LOCK TABLES | Lock_tables_priv | Databases |
PROCESS | Process_priv | Server administration |
PROXY | See proxies_priv table | Server administration |
REFERENCES | References_priv | Databases or tables |
RELOAD | Reload_priv | Server administration |
REPLICATION CLIENT | Repl_client_priv | Server administration |
REPLICATION SLAVE | Repl_slave_priv | Server administration |
SELECT | Select_priv | Tables or columns |
SHOW DATABASES | Show_db_priv | Server administration |
SHOW VIEW | Show_view_priv | Views |
SHUTDOWN | Shutdown_priv | Server administration |
SUPER | Super_priv | Server administration |
TRIGGER | Trigger_priv | Tables |
UPDATE | Update_priv | Tables or columns |
USAGE | Synonym for “no privileges” | Server administration |
The following list provides general descriptions of the privileges available in MySQL. Particular SQL statements might have more specific privilege requirements than indicated here. If so, the description for the statement in question provides the details.
The
ALLorALL PRIVILEGESprivilege specifier is shorthand. It stands for “all privileges available at a given privilege level” (exceptGRANT OPTION). For example, grantingALLat the global or table level grants all global privileges or all table-level privileges.The
ALTERprivilege enables use of theALTER TABLEstatement to change the structure of tables.ALTER TABLEalso requires theCREATEandINSERTprivileges. Renaming a table requiresALTERandDROPon the old table,CREATE, andINSERTon the new table.The
ALTER ROUTINEprivilege is needed to alter or drop stored routines (procedures and functions).The
CREATEprivilege enables creation of new databases and tables.The
CREATE ROUTINEprivilege is needed to create stored routines (procedures and functions).The
CREATE TABLESPACEprivilege is needed to create, alter, or drop tablespaces and log file groups.The
CREATE TEMPORARY TABLESprivilege enables the creation of temporary tables using theCREATE TEMPORARY TABLEstatement.After a session has created a temporary table, the server performs no further privilege checks on the table. The creating session can perform any operation on the table, such as
DROP TABLE,INSERT,UPDATE, orSELECT. For more information, see Section 13.1.18.3, “CREATE TEMPORARY TABLE Syntax”.The
CREATE USERprivilege enables use of theALTER USER,CREATE USER,DROP USER,RENAME USER, andREVOKE ALL PRIVILEGESstatements.The
CREATE VIEWprivilege enables use of theCREATE VIEWstatement.The
DELETEprivilege enables rows to be deleted from tables in a database.The
DROPprivilege enables you to drop (remove) existing databases, tables, and views. TheDROPprivilege is required in order to use the statementALTER TABLE ... DROP PARTITIONon a partitioned table. TheDROPprivilege is also required forTRUNCATE TABLE. If you grant theDROPprivilege for themysqldatabase to a user, that user can drop the database in which the MySQL access privileges are stored.The
EVENTprivilege is required to create, alter, drop, or see events for the Event Scheduler.The
EXECUTEprivilege is required to execute stored routines (procedures and functions).The
FILEprivilege gives you permission to read and write files on the server host using theLOAD DATA INFILEandSELECT ... INTO OUTFILEstatements and theLOAD_FILE()function. A user who has theFILEprivilege can read any file on the server host that is either world-readable or readable by the MySQL server. (This implies the user can read any file in any database directory, because the server can access any of those files.) TheFILEprivilege also enables the user to create new files in any directory where the MySQL server has write access. This includes the server's data directory containing the files that implement the privilege tables. As a security measure, the server will not overwrite existing files. As of MySQL 5.7.17, theFILEprivilege is required to use theDATA DIRECTORYorINDEX DIRECTORYtable option for theCREATE TABLEstatement.To limit the location in which files can be read and written, set the
secure_file_privsystem to a specific directory. See Section 5.1.5, “Server System Variables”.The
GRANT OPTIONprivilege enables you to give to other users or remove from other users those privileges that you yourself possess.The
INDEXprivilege enables you to create or drop (remove) indexes.INDEXapplies to existing tables. If you have theCREATEprivilege for a table, you can include index definitions in theCREATE TABLEstatement.The
INSERTprivilege enables rows to be inserted into tables in a database.INSERTis also required for theANALYZE TABLE,OPTIMIZE TABLE, andREPAIR TABLEtable-maintenance statements.The
LOCK TABLESprivilege enables the use of explicitLOCK TABLESstatements to lock tables for which you have theSELECTprivilege. This includes the use of write locks, which prevents other sessions from reading the locked table.The
PROCESSprivilege pertains to display of information about the threads executing within the server (that is, information about the statements being executed by sessions). The privilege enables use ofSHOW PROCESSLISTor mysqladmin processlist to see threads belonging to other accounts; you can always see your own threads. ThePROCESSprivilege also enables use ofSHOW ENGINE.The
PROXYprivilege enables a user to impersonate or become known as another user. See Section 6.3.10, “Proxy Users”.The creation of a foreign key constraint requires the
REFERENCESprivilege for the parent table.The
RELOADprivilege enables use of theFLUSHstatement. It also enables mysqladmin commands that are equivalent toFLUSHoperations:flush-hosts,flush-logs,flush-privileges,flush-status,flush-tables,flush-threads,refresh, andreload.The
reloadcommand tells the server to reload the grant tables into memory.flush-privilegesis a synonym forreload. Therefreshcommand closes and reopens the log files and flushes all tables. The otherflush-commands perform functions similar toxxxrefresh, but are more specific and may be preferable in some instances. For example, if you want to flush just the log files,flush-logsis a better choice thanrefresh.The
REPLICATION CLIENTprivilege enables the use of theSHOW MASTER STATUS,SHOW SLAVE STATUS, andSHOW BINARY LOGSstatements.The
REPLICATION SLAVEprivilege should be granted to accounts that are used by slave servers to connect to the current server as their master. Without this privilege, the slave cannot request updates that have been made to databases on the master server.The
SELECTprivilege enables you to select rows from tables in a database.SELECTstatements require theSELECTprivilege only if they actually retrieve rows from a table. SomeSELECTstatements do not access tables and can be executed without permission for any database. For example, you can useSELECTas a simple calculator to evaluate expressions that make no reference to tables:SELECT 1+1; SELECT PI()*2;The
SELECTprivilege is also needed for other statements that read column values. For example,SELECTis needed for columns referenced on the right hand side ofcol_name=exprassignment inUPDATEstatements or for columns named in theWHEREclause ofDELETEorUPDATEstatements.The
SELECTprivilege is also needed for tables or views being used withEXPLAIN, including any underlying tables of views.The
SHOW DATABASESprivilege enables the account to see database names by issuing theSHOW DATABASEstatement. Accounts that do not have this privilege see only databases for which they have some privileges, and cannot use the statement at all if the server was started with the--skip-show-databaseoption. Note that any global privilege is a privilege for the database.The
SHOW VIEWprivilege enables use of theSHOW CREATE VIEWstatement. This privilege is also needed for views being used withEXPLAIN.The
SHUTDOWNprivilege enables use of theSHUTDOWNstatement, the mysqladmin shutdown command, and themysql_shutdown()C API function.The
SUPERprivilege enables these operations and server behaviors:Enables configuration changes by modifying global system variables. For some system variables, setting the session value also requires the
SUPERprivilege; if so, it is indicated in the variable description. Examples includebinlog_format,sql_log_bin, andsql_log_off.Enables changes to global transaction characteristics (see Section 13.3.6, “SET TRANSACTION Syntax”).
Enables starting and stopping replication on slave servers, including Group Replication.
Enables use of the
CHANGE MASTER TOandCHANGE REPLICATION FILTERstatements.Enables binary log control by means of the
PURGE BINARY LOGSandBINLOGstatements.Enables setting the effective authorization ID when executing a view or stored program. A user with this privilege can specify any account in the
DEFINERattribute of a view or stored program.Enables use of the
CREATE SERVER,ALTER SERVER, andDROP SERVERstatements.Enables use of the mysqladmin debug command.
Enables
InnoDBkey rotation.Enables reading the DES key file by the
DES_ENCRYPT()function.Enables execution of Version Tokens user-defined functions.
Enables control over client connections not permitted to non-
SUPERaccounts:Enables use of the
KILLstatement or mysqladmin kill command to kill threads belonging to other accounts. (You can always kill your own threads.)The server accepts one connection from a
SUPERclient even if the connection limit controlled by themax_connectionssystem variable is reached.Updates can be performed even when the
read_onlysystem variable is enabled. This applies to table updates and use of account-management statements such asGRANTandREVOKE.The server does not execute
init_connectsystem variable content whenSUPERclients connect.A server in offline mode (
offline_modeenabled) does not terminateSUPERclient connections at the next client request, and accepts new connections fromSUPERclients.
You may also need the
SUPERprivilege to create or alter stored functions if binary logging is enabled, as described in Section 23.7, “Binary Logging of Stored Programs”.The
TRIGGERprivilege enables trigger operations. You must have this privilege for a table to create, drop, execute, or display triggers for that table.When a trigger is activated (by a user who has privileges to execute
INSERT,UPDATE, orDELETEstatements for the table associated with the trigger), trigger execution requires that the user who defined the trigger still have theTRIGGERprivilege.The
UPDATEprivilege enables rows to be updated in tables in a database.The
USAGEprivilege specifier stands for “no privileges.” It is used at the global level withGRANTto modify account attributes such as resource limits or SSL characteristics without naming specific account privileges.SHOW GRANTSdisplaysUSAGEto indicate that an account has no privileges at a privilege level.
It is a good idea to grant to an account only those privileges
that it needs. You should exercise particular caution in granting
the FILE and administrative
privileges:
The
FILEprivilege can be abused to read into a database table any files that the MySQL server can read on the server host. This includes all world-readable files and files in the server's data directory. The table can then be accessed usingSELECTto transfer its contents to the client host.The
GRANT OPTIONprivilege enables users to give their privileges to other users. Two users that have different privileges and with theGRANT OPTIONprivilege are able to combine privileges.The
ALTERprivilege may be used to subvert the privilege system by renaming tables.The
SHUTDOWNprivilege can be abused to deny service to other users entirely by terminating the server.The
PROCESSprivilege can be used to view the plain text of currently executing statements, including statements that set or change passwords.The
SUPERprivilege can be used to terminate other sessions or change how the server operates.Privileges granted for the
mysqldatabase itself can be used to change passwords and other access privilege information. Passwords are stored encrypted, so a malicious user cannot simply read them to know the plain text password. However, a user with write access to theusertableauthentication_stringcolumn can change an account's password, and then connect to the MySQL server using that account.
1) create a dedicated database for temporary tables:
mysql> CREATE DATABASE tmp;
2) Give your users all the access privileges that they need to create and use temporary tables:
mysql> GRANT SELECT, INSERT, UPDATE, DELETE, DROP, ALTER, CREATE TEMPORARY TABLES ON tmp.* TO user@localhost;
Be sure that you do not give them CREATE or GRANT privileges!
3) Have you users create all temporary tables in that 'tmp' database instead of the current database:
mysql> USE mydb
mysql> CREATE TEMPORARY TABLE tmp.dummy SELECT * from mytable;
Your users have to explicitly call their temporary tables as tmp.<tablename> in all requests. There is no problem if two users use the same name for a temporary table since they will not be able to see each other's temporary tables. You can also put the 'tmp' database on a dedicated disk.
SELECT password, host, user,
CONCAT(Select_priv, Lock_tables_priv) AS selock,
CONCAT(Insert_priv, Update_priv, Delete_priv, Create_priv, Drop_priv) AS modif,
CONCAT(Grant_priv, References_priv, Index_priv, Alter_priv) AS meta,
CONCAT(Create_tmp_table_priv, Create_view_priv, Show_view_priv) AS views,
CONCAT(Create_routine_priv, Alter_routine_priv, Execute_priv) AS funcs,
CONCAT(Repl_slave_priv, Repl_client_priv) AS replic,
CONCAT(Super_priv, Shutdown_priv, Process_priv, File_priv, Show_db_priv, Reload_priv) AS admin
FROM USER ORDER BY user, host;
GRANT FILE ON *.* TO 'username'@'host'....
Hope that saves someone else from having to dig for the answer.
If you have WHERE condition " like 'ABC/_%' escape '/' " and you mean select string like 'ABC_'+'something' you'll suddenly find that you got 'ABC'+'something' instead.