Re:Why SELECT * is bad for SQL performance (2020)
by crazygringo on Tuesday February 16, 2021 @01:21PM
(#26157004)
I was thinking more that the process can take hours with large tables (and even longer with replication), you have to be careful it doesn't lock your tables, and basically just a ton of edge cases.
"Crappy wildcard queries" would seem to be the least of it, ha. Most of the time, a wildcard query that returns additional columns at the end won't cause any problems at all -- client software will just ignore them. Unless you're making each row 100x larger in size and you get a performance hit, but that's the point I was making -- that's not something that usually happens in reality anyways.
"Crappy wildcard queries" would seem to be the least of it, ha. Most of the time, a wildcard query that returns additional columns at the end won't cause any problems at all -- client software will just ignore them. Unless you're making each row 100x larger in size and you get a performance hit, but that's the point I was making -- that's not something that usually happens in reality anyways.