:::tip For developer debugging only, do not call this function manually in the production environment. :::
T non_nullable(T expr)
Raise an error if expr is of not nullable, or is of nullable and contains a NULL value. Otherwise, returns the non-nullable data column of the input column.
mysql> select k1, non_nullable(k1) from test_nullable_functions order by k1; +------+------------------+ | k1 | non_nullable(k1) | +------+------------------+ | 1 | 1 | | 2 | 2 | | 3 | 3 | | 4 | 4 | +------+------------------+ mysql> select k1, non_nullable(k1) from test_nullable_functions order by k1; ERROR 1105 (HY000): errCode = 2, detailMessage = [CANCELLED]There's NULL value in column Nullable(Int32) which is illegal for non_nullable mysql> select non_nullable(1); ERROR 1105 (HY000): errCode = 2, detailMessage = [CANCELLED]Try to use originally non-nullable column Int8 in nullable's non-nullable convertion.
non_nullable