question abot primary key

how can I set my primary key to star again from 1?? for example, if I had a
table with some rows in it and I deleted all that rows, next time when I
insert a new row in that table, primary key starts from last primary key of
previous rows, but I want it to start again from 1.

is that possible??

thanks!I think you are talking about an IDENTITY column, which is not the same as a
Primary Key (although IDENTITY is used as a surrogate key).

DBCC CHECKIDENT ('TableName', RESEED,0)

--
David Portas
SQL Server MVP
--|||>> how can I set my primary key to start again from 1? <<

Please read a book on RDBMS; you have absolutely no idea what you are
doing.

Let's get back to the basics of an RDBMS. Rows are not records; fields
are not columns; tables are not files; there is no sequential access
or ordering in an RDBMS, so "first", "next" and "last" are totally
meaningless.

A primary key **BY DEFINITION** is a subset of attributes (columns).
Keys do not "start" anywhere. Each entity in the data model has a
unique primary key by its nature; it is not assigned by the PHYSICAL
storage used to hold the PHYSICAL representation of the DBMS.

If you had a 1950's magnetic tape file, then your question would make
sense. They start at record #1 each time you hang a new magnetic tape
on the drive, which is obviously your mental model. This is the
difference between a VIN number and a parking space number.