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Comment by carbocation | Hacker News Reader

Personal habit is to start my WHERE clause with a TRUE or a FALSE so that adding or removing clauses becomes seamless:

    SELECT foo
    FROM bar
    WHERE TRUE
      AND baz > boom

For OR conditions it's a bit different:

    SELECT foo
    FROM bar
    WHERE FALSE
      OR baz > boom

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this seems like taking on a pretty huge risk for a minor convenience. the difference between those two queries can mean the difference between protecting someone's PII

I'm not sure that I follow. The two queries are to demonstrate difference in form; they are not intended to be equivalent.

If you're already writing:

    WHERE foo=bar
      AND biz=baz

It's not clear to me how:

    WHERE TRUE
      AND foo=bar
      AND biz=baz

is worse.

He’s saying if someone gets in the habit of using that style they have to be very careful. If they forget to change True to False when using an OR that it could have major consequences. Performance being the least of concerns.

I agree that such an error would be of the catastrophic type. It's interesting that several people seem to perceive this formatting approach as something that would increase the risk of that error. Is the red flag for people the WHERE TRUE on one line? Like, would this be less alarming to people?

    WHERE
      TRUE
      AND x=y

I'm so attached to starting all my where clauses with a TRUE (1=1 since SQL Server doesn't have boolean literals) that I do this when I need some OR clauses:

    SELECT foo
    FROM bar
    WHERE 1=1
      AND (1<>1
           OR baz > boom
           OR fizz >= bang
           )
      AND foo is not null

So you can comment out lines starting with OR individually. Some people might hate it but it makes sense conceptually for me since almost every query I write takes a chain of ANDs in the where clause as a starting point.

Yeah, I almost always do "where 1=1" with the actual expressions AND'ed below.

For OR, I like to keep the "1=1" and do

    AND (1=2
      OR ...
    )

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