[ES|QL] FUSE command fails when a column contains NULL #137544
Description
If a column is NULL, FUSE fails with:
{
"error": {
"root_cause": [
{
"type": "esql_illegal_argument_exception",
"reason": "illegal data type [null]"
}
],
"type": "esql_illegal_argument_exception",
"reason": "illegal data type [null]"
},
"status": 500
}
Reproduction:
POST my-index/_doc
{
"id": "park_rocky-mountain",
"title": "Rocky Mountain",
"description": "Bisected north to south by the Continental Divide, this portion of the Rockies has ecosystems varying from over 150 riparian lakes to montane and subalpine forests to treeless alpine tundra."
}
POST _query?format=txt
{
"query": """
FROM my-index METADATA _id, _index, _score |
EVAL input = null |
EVAL tm = CASE(input is NULL, \"\", input) | WHERE tm==\"\" OR MATCH(title, tm) |
FORK
(WHERE title:\"rocky\" | SORT _score DESC)
(WHERE description:\"rocky\" | SORT _score DESC) |
FUSE |
LIMIT 10
"""
}
Dropping the NULL column before FUSE solves the issue:
POST _query?format=txt
{
"query": """
FROM my-index METADATA _id, _index, _score |
EVAL input = null |
EVAL tm = CASE(input is NULL, \"\", input) | WHERE tm==\"\" OR MATCH(title, tm) |
FORK
(WHERE title:\"rocky\" | SORT _score DESC)
(WHERE description:\"rocky\" | SORT _score DESC) |
DROP input
FUSE |
LIMIT 10
"""
}