mysql - Optimal way to fill in missing values after a LEFT JOIN? -

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i simplify problem make core issue clear: have query tablea inner join tableb left join tablec.

the result of left join in result set, 2 of columns might have null values in rows. fill in missing values have loop on result set , query database has data (so not possible join in first place).

my question is: there standard/optimised approach when need fill nulls of result set after left join?

you can use coalesce(...) (msdn - coalesce) instead.

you query like:

select a, b, coalesce(tableb.c, 'replacement value') tablea inner join tableb left join tablec ...

add join replacement table , put column want replace null values in coalesce function in don't want use static value.


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