in reply to poll ideas quest 2012
The (redundant) predicate in a SQL EXISTS() predicate should be "SELECT ?":
- * -- Nothing says "i don't care" like a good asterisk
- 1 -- "Everyone knows" asterisk causes a useless data dictionary lookup
- '1' -- Characterizes a number one idea
- NULL -- Why SELECT anything at all?
- 'NULL' -- Null strings are best
- '/dev/null' -- In case you nix the other ideas
- 'NUL' -- Used in all Windows of opportunity
- Avoid the issue by using IN() stead
- Convolute the issue by doing a join