I think that this string "0 but true" is a very ancient artifact dating from before scientific notation. I have never seen this in my coding. I have however encountered "0E0" with the DBI as the normal, standard way to say "statement worked correctly, but produced a zero result", true in a logical comparison sense, but numeric zero in a numeric sense.

"0 but true" is the self-documenting way to have a zero value evaluating to true, "0E0" is the clever but not so obvious one.

Alexander

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Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)

I am not the judge or the author of either one of these variations. I simply report that 0E0 is in current use.