Redundant boolean CASE WHEN

I’m sure you have all seen these as I see them often!

select
    case
        when n > 0 then true else false end as is_positive
from table_a

I would like to add a rule to prefer

select
    n > 0 as is_positive
from table_a

A case when statement is redundant if it uses only one when which is turned into true or false

However, to add a “fix” the rule should also take in account the following:

select
    case
        when n >= 0 then false else true end as is_negative
from table_a

which should be turned into

select
    case
        not(n >= 0) as is_negative
from table_a

[dmateusp]

hey so your code shouldn’t be breaking that rule, this rule should only apply to CASE WHENs that have a true/false return statement

I would say the statement you quoted is actually false ^^, I didn’t write

A case when statement is redundant if it uses only one when

I wrote

A case when statement is redundant if it uses only one when >> which is turned into true or false <<

That last piece might be unclear but see the examples in the description of the PR, that’s the cases that this rule aimed to fix.

It seems like a bug with the rule, which should be opened as a separate issue

thanks 😃

[dmateusp]

@rbetzler it’s not spam! Just go ahead an open the PR ^^, then we can have a discussion there.

You documented + tested the rule so I’d say it’s a 🥇 first go