diff --git a/pandas/core/reshape/merge.py b/pandas/core/reshape/merge.py index f0848214119e16..2b18321b666ad5 100644 --- a/pandas/core/reshape/merge.py +++ b/pandas/core/reshape/merge.py @@ -165,8 +165,7 @@ def merge_ordered(left, right, on=None, `left` and `right` respectively. Pass a value of `None` instead of a string to indicate that the column name from `left` or `right` should be left as-is, with no suffix. At least one of the - values must not be None. A combination of `''` and `None` is will - raise error for columns which type is string + values must not be None. how : {'left', 'right', 'outer', 'inner'}, default 'outer' * left: use only keys from left frame (SQL: left outer join) * right: use only keys from right frame (SQL: right outer join)