<< DECLARE GLOBAL TEMPORARY TABLE statement | ON ROLLBACK DELETE ROWS >>

Temporary tables are useful when

<< DECLARE GLOBAL TEMPORARY TABLE statement | ON ROLLBACK DELETE ROWS >>

Derby Reference Manual

These tables do not reside in the system catalogs and are not persistent. Temporary
tables exist only during the connection that declared them and cannot be referenced
outside of that connection. When the connection closes, the rows of the table are deleted,
and the in-memory description of the temporary table is dropped.

Temporary tables are useful when:

· The table structure is not known before using an application.
· Other users do not need the same table structure.
· Data in the temporary table is needed while using the application.
· The table can be declared and dropped without holding the locks on the system

catalog.

Syntax

DECLARE GLOBAL TEMPORARY TABLE

table-Name

{ column-definition [ , column-definition ] * }
[ ON COMMIT {DELETE | PRESERVE} ROWS ]
NOT LOGGED [ON ROLLBACK DELETE ROWS]

table-Name

Names the temporary table. If a schema-Name other than SESSION is specified, an
error will occur (SQLSTATE 428EK). If the schema-Name is not specified, SESSION
is assigned. Multiple connections can define declared global temporary tables with the
same name because each connection has its own unique table descriptor for it.

Using SESSION as the schema name of a physical table will not cause an error, but is
discouraged. The SESSION schema name should be reserved for the temporary table
schema.

column-definition

See

column-definition

for

CREATE TABLE

for more information on

column-definition

DECLARE GLOBAL TEMPORARY TABLE

does not allow

generated-column-spec

in the

column-definition

Data type
Supported data types are:

· BIGINT
· CHAR
· DATE
· DECIMAL
· DOUBLE
· DOUBLE PRECISION
· FLOAT
· INTEGER
· NUMERIC
· REAL
· SMALLINT
· TIME
· TIMESTAMP
· VARCHAR

ON COMMIT

Specifies the action taken on the global temporary table when a COMMIT operation is
performed.

DELETE ROWS

All rows of the table will be deleted if no hold-able cursor is open on the table. This is
the default value for ON COMMIT. If you specify ON ROLLBACK DELETE ROWS, this