mysql - Why does UPDATE x SET y='c' AND TRUE result in y='0' -

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i'm playing around sql challenge , noticed given table x single text column y following query:

update x set y='c' , true

results in y='0'

also:

update x set y='c' or true

results in y='1'

out of curiosity i'm trying understand what's happening underneath produce these results.

expressions y='c' , true , y='c' or true boolean expressions. evaluate either 1 when expression true, or 0, when expression false.

your update evaluates these expressions, , stores results in field y.


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