Hi Guys, We are experiencing a break in backward compatibility with the lastest 10.1 release which got publied on the debian/stretch release. Queries that worked before suddenly spit errors about unknown column. It seems to be related to the use of "inner join" without on/using clause and left join and 'extra table': SELECT * FROM t1, t2 INNER JOIN t3 LEFT JOIN t4 ON t4.id = t3.id_t5 WHERE t3.id = t2.id_t3 AND t1.id = X will give: ERROR 1054 (42S22): Unknown column 't1.id' in 'where clause' Adding parenthesis around the join: SELECT * FROM t1, ( t2 INNER JOIN t3 LEFT JOIN t4 ON t4.id = t3.id_t5 ) WHERE t3.id = t2.id_t3 AND t1.id = X or adding an "on" clause on the inner join seem to fix the issue SELECT * FROM t1, t2 INNER JOIN ON t3.id = t2.id_t3 t3 LEFT JOIN t4 ON t4.id = t3.id_t5 WHERE t1.id = X Weirdly enough it's impossible to have a Left join without on/using clause, while the parser let us write an inner join without. I cannot find a related note in the changelogs ..