Subquery returned more than 1 row error

[jfcox]

I have a table with three columns; column a is an identity column, column b is just an id number, and column c is a date. I have several blanks in the date column and want to replace them with nulls. I tried the following query which fails on a "subquery returned more than 1 row" error and I just don't get it.

Update MyTable
set ColumnC = NULL
where columnC = ''

I also tried:
Update MyTable
set ColumnC = NULL
where columnC = '' and columA in (a hardcoded list of values I put in manually)


I'm sure there is a simple answer but I just don't see it. Any help appreciated!

Jim

 

[philhege]

Try

UPDATE Mytable
SET ColumnC = NULL
Where ColumnA IN(select ColumnA from Mytable
WHERE ColumnC = '')


Phil Hegedusich
Senior Programmer/Analyst
IIMAK

http://www.iimak.com

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