ALTER TABLE statement (SAP Library - Reference Manual 7.2 (BC))

ALTER TABLE statement

An ALTER TABLE statement ( alter_table_statement ) changes the properties of a base table (see Table).

Syntax

<alter table statement> ::=
ALTER TABLE <table_name> <add_definition>
| ALTER TABLE <table_name> <drop_definition>
| ALTER TABLE <table_name> <alter_definition>
| ALTER TABLE <table_name> <modify_definition>
| ALTER TABLE <table_name> <referential_constraint_definition>
| ALTER TABLE <table_name> DROP FOREIGN KEY <referential_constraint_name>
| ALTER TABLE <table_name> <sample_definition>

add definition, drop definition, alter definition, modify definition, referential constraint definition, referential constraint name, sample definition

Explanation

The table name must be the name of an existing base table. The table must not be a temporary base table. The current user must have the ALTER privilege for the specified table.

If a referential CONSTRAINT definition was specified, a new referential constraint is defined for the base table. The rules described in the referential CONSTRAINT definition apply.

If DROP FOREIGN KEY was specified, the referential CONSTRAINT definition identified by the name of the referential constraint is dropped.

If a SAMPLE definition is specified, a new number of rows is defined and is taken into account by the database system when the table statistics are calculated.