Copy one column to another

I have a table I need to make changes to. Dropping columns isn't my problem, but before I drop one of the columns I need to copy the values that aren't null to another existing column in the same table. So for psuedo-code it would be something like:

update Mapping Set SID = (select SMappingID from Mapping where SMappingID is not null)

I don't know if I should be doing this in a loop (which I'm not totally familiar with using) or if there is a better way to copy these values. If it helps my columns are -

ID (int, Not Null, PK)
SID (int, Not Null, FK)
PartID (int, Not Null, FK)
CompID (int, Not Null)
SMappingID (int, Null)

Quote:

Originally Posted by NamelessNumberheadMan

I have a table I need to make changes to. Dropping columns isn't my problem, but before I drop one of the columns I need to copy the values that aren't null to another existing column in the same table. So for psuedo-code it would be something like:

update Mapping Set SID = (select SMappingID from Mapping where SMappingID is not null)

I don't know if I should be doing this in a loop (which I'm not totally familiar with using) or if there is a better way to copy these values. If it helps my columns are -

ID (int, Not Null, PK)
SID (int, Not Null, FK)
PartID (int, Not Null, FK)
CompID (int, Not Null)
SMappingID (int, Null)

try:
update Mapping Set SID = SMappingID
where SMappingID IS NOT NULL|||

Quote:

Originally Posted by NamelessNumberheadMan

I have a table I need to make changes to. Dropping columns isn't my problem, but before I drop one of the columns I need to copy the values that aren't null to another existing column in the same table. So for psuedo-code it would be something like:

update Mapping Set SID = (select SMappingID from Mapping where SMappingID is not null)

I don't know if I should be doing this in a loop (which I'm not totally familiar with using) or if there is a better way to copy these values. If it helps my columns are -

ID (int, Not Null, PK)
SID (int, Not Null, FK)
PartID (int, Not Null, FK)
CompID (int, Not Null)
SMappingID (int, Null)

The query is simple:

UPDATE TABLENAME
SET NEWCOLUMN = SOURCECOLUMN WHERE SOURCECOLUMN IS NOT NULL.

Thanks.