About Locking in SQL2000

[Sepahram]

Hey all,
I have a table and two following transactions:

Table11 ( DD int , CC int ) -- with no PK or index ...

BEGIN TRAN 1
INSERT INTO Table11 VALUES ( 6 , 6 )

-- ROLLBACK TRAN 1
-- COMMIT TRAN 1

BEGIN TRAN 1
SELECT * FROM Table11 WHERE DD = 1
-- ROLLBACK TRAN 1
-- COMMIT TRAN 1

I execute the first and reveiw the lock info as below:

spid dbid ObjId IndId Type Resource Mode Status
------ ------ ----------- ------ ---- ---------------- -------- ------
76 5 0 0 DB S GRANT
76 5 379148396 0 RID 1:159:4 X GRANT
76 5 0 0 PAG 1:159 IX GRANT
76 1 85575343 0 TAB IS GRANT
76 5 379148396 0 TAB IX GRANT

I have no index on the table. When I execute the second tran before I commit or rollback the first one , it gets blocked. Why?

By the way it doesn't happen when I create a PK , unique constraint or index on DD
Amir,