Topic: Sampling of a nonzero field
I get acquainted with SQL. There was a simple task. It is necessary to make SELECT to two fields, but to return only the nonzero.
I do while so. I write on PL SQL for Si, therefore I ask not to pay attention to syntax singularities
SELECT VAR1, VAR2
WHERE KEY =:key;
That is now I fill both Si-variables var1 and var2, I analyze them in the code on NULL further. I want to understand, how at level SQL to write a condition that if one field NULL to select the second.
In advance thanks for the help!