- Data Stored in GTT are temporary
- The data stored in GTT exist only as long as the session or Transaction. At the end all the data is automatically deleted.
- Data is private for each sessions.
- Table definition is viewed by all sessions.
- Temporary data is stored into default temp tablespace, which can also be specified while creating the table definition.
- We can perform insert update and delete on these tables.
Uses of GTT
- When we need to perform high level calculation and for temporary purpose and store the value we used GTT
- The data need not be persisted
- Other users need not see the data in the table
create GLOBAL TEMPORARY TABLE GTT_COUNTRY( COUNTRY_ID NUMBER, COUNTRY_NAME VARCHAR2(30) ) ON COMMIT PRESERVE ROWS; --Data is present until the connection/session exist --) ON COMMIT DELETE ROWS; --Data is deleted on commit select * from GTT_COUNTRY; insert into GTT_COUNTRY values (1,'India'); insert into GTT_COUNTRY values (2,'USA'); insert into GTT_COUNTRY values (3,'UK'); --insert update delete can be performed on GTT