How to delete all rows data from database

Question

Hello All.
I have a database username 'abc'. This database contain 123 tables & have many data.
I want to empty all the database. Is it possible that clear all the database with a single query.
if yes then kindly tell me about the query .
Thanks
Diamond

Answer 1

Keep in mind that you cannot rollback the truncate command.
Once you truncate a table all of it's data AND statistics are gone.
If you do not want to use PL/SQL to delete all rows you can generate a script by SQL
SCOTT@ORCL> SELECT ' TRUNCATE TABLE '|| TABLE_NAME||';' FROM USER_TABLES;
'TRUNCATETABLE'||TABLE_NAME||';'
TRUNCATE TABLE BONUS;
TRUNCATE TABLE SALGRADE;
TRUNCATE TABLE DEPT_LOV;
TRUNCATE TABLE TITLE;
TRUNCATE TABLE TEST_DATE;
TRUNCATE TABLE DEPT;
TRUNCATE TABLE REP;
TRUNCATE TABLE REP_PARAM;
TRUNCATE TABLE EMP;
10 rows selected.
SCOTT@ORCL> SELECT 'DELETE FROM '|| TABLE_NAME||';' FROM USER_TABLES;
'DELETEFROM'||TABLE_NAME||';'
DELETE FROM BONUS;
DELETE FROM SALGRADE;
DELETE FROM DEPT_LOV;
DELETE FROM TITLE;
DELETE FROM TEST_DATE;
DELETE FROM DEPT;
DELETE FROM REP;
DELETE FROM REP_PARAM;
DELETE FROM EMP;
10 rows selected.
SCOTT@ORCL>You can save the output in a .sql file and run it.
Regards,
Tony