"Marcos" <mjs_ops@xxxxxxx> wrote > > I always think that use of * in SELECT affected in the performance, > becoming the search slowest. > > But I read in the a Postgres book's that it increases the speed of > search. > > And now???? What the more fast? > If you mean use "*" vs. "explicitely name all columns of a relation", then there is almost no difference except the negligible difference in parsing. If you mean you just want part of the columns of a relation but you still use "*": Yes, you will save one projection operation for each result row but you will pay for more network traffic. In the worst case, say your "*" involves some toast attributes, you just hurt performance. Considering the benefits is so marginal and dangerous, I suggest stay with the idea that "only retrive the columns that you are interested in". Regards, Qingqing
