That doesn't matter. The json_extract function returns a string, so json_extract('[{"foo": "x"}]', '$.foo') is NULL and json_extract('[{"foo": "x"}]', '$[0].foo

That doesn't matter. The json_extract function returns a string, so json_extract('[{"foo": "x"}]', '$.foo') is NULL and json_extract('[{"foo": "x"}]', '$[0].foo') is 'x' and it doesn't matter if this is destined to go into a generated column or an index. [append] And SQLite's json_extract doesn't have anything like '$[*].foo' or any mapping functions. You could use json_each to do that, but the process is very different from creating an index.