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is_excluded = 1 is very different from do_not_touch != 1. Whenever possible, try to structure your data and queries so that you can do an equi-join - that is, compare things using an = comparison. ...
Answer
#1: Initial revision
by
BobJarvis
·
2020-08-11T19:08:59Z (about 4 years ago)
`is_excluded = 1` is very different from `do_not_touch != 1`. Whenever possible, try to structure your data and queries so that you can do an equi-join - that is, compare things using an `=` comparison. `>` and `<` and `!=` can be really bad because the database will at the very least have to do an index scan, if there's an appropriate index available - if not, full table scan, baby! Wooo! If you can use `do_not_touch = 0` that would be nice, but I obviously have no idea what that field contains.
Also, it helps to have an appropriate index. For your second query
UPDATE example_table
SET textfield = 'X'
WHERE textfield = 'Y'
and do_not_touch != 1
it would seem that an index on `example_table(textfield, do_not_touch)` would perhaps be helpful.