Thread: How can we Empty the whole tables by one single query

Meh... don't let users have access to the tables... have a good backup strategy!!

Respected, But I have given the Relations to Tables. Thanks.

You could have specified that in the post.. How can one come to know that you want to perform a CASCADE DELETION ? e.g. CREATE TABLE tblPK ( id int primary key ) CREATE TABLE tblFK (id int , name varchar( 50 ), age int FOREIGN KEY (id) REFERENCES tblPK ON DELETE CASCADE )

I always envisage someone going to the settings table and using cascade delete on the Standard Customer record or something. Scared does not even cover it, terrified is closer.

Drop database: The DROP DATABASE statement is used to delete a database. Everything is deleted ... tables, views, indexes, stored procedures, etc Drop Table: The DROP TABLE statement is used to delete a table. Truncate Table: Delete the data inside the table, and not the table itself Use this as reference: http://www.w3schools.com/SQl/sql_drop.asp [ ^ ]

Thats even the worst side effect. Imagine a header table with, lets say, 1000 records in it. Each header has 100,000 (badly indexed) child records. Cascade delete is turned on. Someone comes along and says "Ah header table only has 1000 rows, it will be easy to delete a record from there". Database reduced to treacle.

Probably for the same reason as I haven't - we are control freaks who like to explicitly delete things when we want to, not sudenly finding it happening 'on its own'