Sybase 12.4.2 manual Dropping tables, 124, To drop a table in Sybase Central

Working with tables

Altering tables in Sybase Central

Altering tables in a join index

The property sheets for tables and columns display all the table or column attributes. You can alter a table definition in Sybase Central by displaying the property sheet for the table or column you wish to change, altering the property, and clicking OK to commit the change.

You cannot ADD, DROP or MODIFY a base table column that participates in a join condition of a join index. To alter joined columns, you must first drop the join index, alter the table, and then recreate the join index. See “Using join indexes” for complete information on join indexes.

Dropping tables

The following DROP TABLE statement deletes all the records in the skill table and then removes the definition of the skill table from the database

DROP TABLE skill

Like the CREATE statement, the DROP statement automatically executes a COMMIT before and after dropping the table. This makes permanent all changes to the database since the last COMMIT or ROLLBACK.

The DROP statement also drops all indexes on the table, except if any column in the table participates in a join index.

If you only want to remove data rows but not the table itself, use the TRUNCATE TABLE statement. If you truncate a table while other users are reading from it, the normal rules of table versioning apply, that is, old table versions remain until readers' transactions complete; see Chapter 8, “Transactions and Versioning” for details.

DROP TABLE and TRUNCATE TABLE are very fast, taking only seconds to occur. The size of the data does not effect the speed of the operation.

For a full description of the DROP statement, see Adaptive Server IQ Reference

Manual.

❖To drop a table in Sybase Central:

1 Connect to the database.

2 Click the Tables folder for that database.

3 Right-click the table you wish to delete, and select Delete from the pop-up menu.

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