Jose Isaias Cabrera, on Friday, November 1, 2019 11:51 AM, wrote... > > > 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.
So, I got it to work in 3 rows, select count(n) from t0 UNION ALL Select count(n) FROM t1 UNION ALL SELECT count(n) FROM t2; 15 15 15 But, is there a way to get it to work on one row? Sorry for the newbie post. Thanks. josé _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
