delete all data

How do you delete all data? The simplistic approach would be to truncate all tables SQL> select table_name from user_tables; TABLE_NAME ———- T1 SQL> truncate table t1; Table truncated. You cannot truncate if you have referential integrity constraints. SQL> truncate table t2; ORA-02266: unique/primary keys in table referenced by enabled foreign keys Ok, let’s disable […]

DELETE is faster than TRUNCATE

Truncate is useful in some serial batch processing but it breaks the read-write consistency, generates stranges errors and results for running selects, and it needs DROP ANY TABLE when run over a table that you do not own. But also, DELETE is faster in the following test case. In 12c, you could have over one […]