Marios Trivyzas 3bee647e5b
SQL: Fix issue with DataType for CASE with NULL (#46173)
Previously, if the DataType of all the WHEN conditions of a CASE
statement is NULL, then it was set to NULL even if the ELSE clause
has a non-NULL data type, e.g.:
```
CASE WHEN a = 1 THEN NULL
           WHEN a = 5 THEN NULL
ELSE 'foo'
```

Fixes: #46032
(cherry picked from commit 8c1012efbbd3a300afd0dfb9b18250f15ea753f9)
2019-09-02 11:17:24 +03:00
..
2019-08-23 10:39:39 +02:00