Contents
Why does DROP database take so long?
The DROP DATABASE command probably waited for the database to finish importing before it ran. So, rather than DROP DATABASE taking a long time, it was probably just the import.
Why is TRUNCATE table taking so long?
For some reason, the TRUNCATE TABLE command takes really long time to execute (both on the master and on the slave). It takes about 400K ms to execute!! When it runs on the slave, it causes it to lag from the Master. After the TRUNCATE TABLE finishes, everything is back to normal.
Does dropping a table DROP triggers?
DROP TABLE always removes any indexes, rules, triggers, and constraints that exist for the target table. However, to drop a table that is referenced by a view or a foreign-key constraint of another table, CASCADE must be specified.
Is TRUNCATE faster than DROP?
TRUNCATE is a DDL(Data Definition Language) command. It is used to delete all the tuples from the table. The TRUNCATE command is faster than both the DROP and the DELETE command. Like the DROP command we also can’t rollback the data after using the this command.
How do I force drop a table in MySQL?
If you are using phpmyadmin then this feature is already there.
- Select the tables you want to drop.
- From the dropdown at the bottom of tables list, select drop.
- A new page will be opened having checkbox at the bottom saying “Foreign key check”, uncheck it.
- Confirm the deletion by accepting “yes”.
Can we rollback TRUNCATE?
You cannot ROLLBACK TRUNCATE Simply, you cannot rollback a transaction if it is already committed but you can do something else to get the data back (or at least some parts of it). When you execute the TRUNCATE statement, your data is still in the MDF file.
Can we rollback after delete?
The operation cannot be rolled back. DROP and TRUNCATE are DDL commands, whereas DELETE is a DML command. DELETE operations can be rolled back (undone), while DROP and TRUNCATE operations cannot be rolled back.
Why does truncate or drop table take so long?
The seems to be the most likely reason for DROP/TRUNCATE taking a long time. Run sp_who2 and check the values in tbe Blk column. Any non-zero value in that column is the spid blocking the spid on that row. So check if any blocked spid is your TRUNCATE/DROP process.
Is there a way to drop a table?
Tony C. Dropping or Truncating a table is instantaneous once you acquire the an exclusive schema lock on the table (Sch-M). You can see which sessions hold incompatible locks on the table by querying sys.dm_tran_locks. You can then wait for those sessions to finish with the table, or kill them.
How can I drop a table in PostgreSQL?
Find its pid. You can terminate a backend with the query SELECT pg_terminate_backend (64738), where 64738 is the pid column in your previous SELECT. After that, you can likely DROP that table. If even that won’t work, then restart postgresql, but most likely it will.