Issue on docs

[nzzl6]

Path:/zh-CN/docs/sql-manual/sql-functions/aggregate-functions/min-by

+------+------+------+------+ | k1 | k2 | k3 | k4 | +------+------+------+------+ | 0 | 3 | 2 | 100 | | 1 | 2 | 3 | 4 | | 4 | 3 | 2 | 1 | | 3 | 4 | 2 | 1 | +------+------+------+------+

select min_by(k1, k4) from tbl;

+--------------------+ | min_by(k1, k4) | +--------------------+ | 4 | +--------------------+

如何得出最小的k4对应的最小的k1，如上就是得出3？