[DRILL-4754] Missing values are not missing

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Assignee: Unassigned
• Reporter: Ted Dunning
• Created: 27/Jun/16 03:50
• Updated: 19/Jun/17 19:27

Description

If I have a query which reads from a JSON file where a field is a list or is missing, then the records where the field should missing will instead have a value for that field that is an empty list:

0: jdbc:drill:> select * from maprfs.ted.`bug.json`;
+----+--------+------+
| *a*  |   *b*    |  *c*   |
| 3  | [3,2]  | xyz  |
| 7  | []     | wxy  |
| 7  | []     | null  |
+----+--------+------+
2 rows selected (1.279 seconds)

where the file in question contains these three records:

{'a':3, 'b':[3,2], 'c':'xyz'}
{'a':7, 'c':'wxy'}
{"a":7, "b":[]}

The problem is in the second record of the result. I would have expected b to have had the value NULL.

I am using drill-1.6.0.

Issue Links

• is related to: DRILL-4824 Null maps / lists and non-provided state support for JSON fields. Numeric types promotion.
• relates to: DRILL-1646 Drill cannot handle empty array/list types in JSON documents
• relates to: DRILL-1767 Add support for nullable maps