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www.it-ebooks.infoCHAPTER 29 • SECURING MYSQLThe tables_priv TableThe tables_priv table is intended to store table-specific user privileges. It comes into play only if theuser, db, and host tables do not satisfy the user’s task request. To best illustrate its use, consider anexample. Suppose that user jason from host example.com wants to execute an UPDATE on the table stafflocated in the database company. Once the request is initiated, MySQL begins by reviewing the usertable to see if jason@example.com possesses global INSERT privileges. If this is not the case, the db and hosttables are next reviewed for database-specific insertion privileges. If these tables do not satisfy therequest, MySQL then looks to the tables_priv table to verify whether user jason@example.com possessesthe insertion privilege for the table staff found in the company database.An overview of the tables_priv table is found in Table 29-4.Table 29-4. Overview of the tables_priv TableColumn Datatype Null DefaultHost char(60) No No defaultDb char(64) No No defaultUser char(16) No No defaultTable_name char(64) No No defaultGrantor char(77) No No defaultTimestamp timestamp Yes Current timestampTable_priv tableset No No defaultColumn_priv columnset No No default* Because of space limitations, the term tableset is used as a placeholder for set(Select, Insert,Update, Delete, Create, Drop, Grant, References, Index, Alter, Create view, Show view,Trigger). The term columnset is a placeholder for set(Select, Insert, Update, References).All the columns found in the tables_priv table should be familiar, except the following:• Table_name: Determines the table to which the table-specific permissions setwithin the tables_priv table will be applied.• Grantor: Specifies the username of the user granting the privileges to the user.• Timestamp: Specifies the exact date and time when the privilege was granted to theuser.• Table_priv: Determines which table-wide permissions are available to the user.The following privileges can be applied in this capacity: SELECT, INSERT, UPDATE,DELETE, CREATE, DROP, GRANT, REFERENCES, INDEX, ALTER, CREATE VIEW, SHOW VIEW, andTRIGGER.571