Hello,
I want to implement something like Col3 = Col2 + Col1 in SQL.
This is somewhat similar to Excel, where every value in column 3 is sum of corresponding values from column 2 and column 1.
+2
A:
Yes, you can do it in SQL using the UPDATE command:
UPDATE TABLE table_name
SET col3=col1+col2
WHERE <SOME CONDITION>
This assumes that you already have a table with populated col1 and col2 and you want to populate col3.
codaddict
2010-03-10 08:25:18
You can also do it in a SELECT statement - it doesn't have to be just part of an UPDATE
Tim Drisdelle
2010-03-10 08:30:07
and actually, storing a calculated value usually breaks normalization rules
Leslie
2010-03-10 14:55:45
+2
A:
Have a look at Computed Columns
A computed column is computed from an expression that can use other columns in the same table. The expression can be a noncomputed column name, constant, function, and any combination of these connected by one or more operators.
Also from CREATE TABLE point J
Something like
CREATE TABLE dbo.mytable
( low int, high int, myavg AS (low + high)/2 ) ;
astander
2010-03-10 08:25:49
+2
A:
Yes. Provided it is not aggregating data across rows.
assume that col1 and col2 are integers.
SELECT col1, col2, (col1 + col2) as col3 FROM mytable
Tim Drisdelle
2010-03-10 08:26:09