Deleting Data

The DELETE statement deletes the specified record/row from the specified table.
Syntax:

DELETE FROM table_name
WHERE some_column = some_value;

The above syntax is just one way to represent this statement. The "where" clause can contain any combination of operators and as many conditions as needed. The omition of the "where" clause causes all the records in the table to be deleted since it's the "where" clause which specifies which records have to be deleted. So be careful !!

Example:

ssn	fname	lname	address	city	state
512687458	Joe	Smith	83 First Street	Howard	Ohio
758420012	Mary	Scott	842 Vine Ave.	Losantiville	Ohio
102254896	Sam	Jones	33 Elm St.	Paris	New York
876512563	Sarah	Ackerman	440 U.S. 110	Upton	Michigan

Suppose we want to delete the record of Joe Smith. The query for the same would be:

DELETE FROM Emp_Add
WHERE fname = 'Joe' AND lname = 'Smith';

The resultant table will be:

ssn	fname	lname	address	city	state
758420012	Mary	Scott	842 Vine Ave.	Losantiville	Ohio
102254896	Sam	Jones	33 Elm St.	Paris	New York
876512563	Sarah	Ackerman	440 U.S. 110	Upton	Michigan

This SQL query will delete all the records that have fname as Joe and lname as Smith. Had there been another row having the same fname and lname, it would have been deleted as well. In case you forget to put the WHERE clause, all the records in the Emp_Add table will be deleted. So be careful. !!