Richard Hipp, on Friday, November 1, 2019 11:41 AM, wrote...
>
> On 11/1/19, Jose Isaias Cabrera, on
> > sqlite> select count(a.n),count(b.n),count(c.n) FROM t0 AS a LEFT JOIN t1 AS
> > b LEFT JOIN t2 AS c;
> > 3375|3375|3375
> >
> > Huh?  I expected the result:
> >
> > 15|15|15
>
> You did a three-way join on tables with 15 rows each.  15x15x15 is 3375.
>
> A LEFT JOIN without an ON clause is just a JOIN.  Or, to view it
> another way, it is the same as having "ON true" on each LEFT JOIN.
> LEFT JOIN only differs from JOIN when the ON clause evaluates to false
> or NULL, in which case the right table of the LEFT JOIN pretends to be
> a table of a single row of all NULL values.

Thanks, Dr. Hipp.  Now I understand why the real query hung, and didn't produce 
a response.  Sorry for the lack of knowledge. :-)  Anyone, out there, how do I 
get the record count of three tables in one call?  Thanks.

josé
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