Re: INSERT WHERE NOT EXISTS

Karsten Hilbert wrote:

// check if entry already exists
SELECT COUNT(*) FROM tablename WHERE [cond]   

You may want to try this instead:
select exists(select * from tablename where [cond])

which should be faster than count(*). You'll get back a
boolean value, though, not an integer.

Karsten 

Why not do:
 SELECT 1 FROM tablename WHERE [cond];

  And use row_count > 0 to determine a hit.

And I can't think of a way to prevent the race-condition thing besides using SERIALIZABLE ISOLATION.