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Showing posts with the label changing table name in mysql

Viewing MySQL Metadata

The INFORMATION_SCHEMA is a virtual database that is automatically created and populated by MySQL, there is no need to create an INFORMATION_SCHEMA database. There also is no associated file structure due to the fact that the contents of the data are actual views, rather than logical data being stored in any one location. Only SELECT statements are allowed against the tables in the INFORMATION_SCHEMA database. The following SELECT example demonstrates some of the metadata that can be viewed: <?php // Load variables used in mysql_connect and connect to server include "connect_info.php"; $linkID1 = mysql_connect($dbhost,$dbuser,$dbpass) or die("Could not connect to MySQL server"); // Execute Query to Collect Metadata $query = "SELECT TABLE_NAME, ENGINE, TABLE_ROWS, UPDATE_TIME FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_SCHEMA='world'"; $results = mysql_query($query, $linkID1); // Build HTML Table of Results print "<table

Altering Tables ( Renaming Tables )

Renaming a table changes neither a table's structure nor its contents. The following statement renames table t1 to t2: ALTER TABLE t1 RENAME TO t2; Another way to rename a table is by using the RENAME TABLE statement: RENAME TABLE t1 TO t2; RENAME TABLE has an advantage over ALTER TABLE in that it can perform multiple table renames in a  single operation. One use for this feature is to swap the names of two tables: RENAME TABLE t1 TO tmp, t2 TO t1, tmp TO t2; For TEMPORARY tables, RENAME TABLE does not work. The ALTER TABLE command must be used  instead.