SQL question

I know how to do simple stuff in MS-SQL. But, I need to make a database change
that I am not confident about.

The database is on an MS-SQL server.

I realize this is not a Midrange-specific question, and I apologize for that.

Basically, I need to populate two columns in one table with corresponding values
from another table. But only under specific circumstances.

I do not want to change the first table's values if they are already populated.
In the case of this database, there can be no valid dates prior to 11/01/1999.
The database design is not mine. The vendor is using two date-time columns,
one stores actual date and a time of zero. The second stores the default date
1/1/1800 and the actual time.

What I have come up with, I present below. It is incomplete. I do not know how
to specify the second table properly. The two tables are POST_PROCEDURE which I
want to selectively update, and POST_ANESTHESIA_TYPE, which has the data I need.

The two tables have a common column, CASE_NO.


Any help is appreciated.

Here is what I have come up with:

UPDATE POST_PROCEDURE p
SET p.START_DATE = , p.START_TIME =
WHERE p.CASE_NO = a.CASE_NO
AND p.PROCEDURE_ID = '131200'
AND p.START_DATE < '11/01/1999'

John McKee