Help with Array(JSON) serialization. Getting inconsistent results.

[pcarrotta]

Asking here instead of Bug Fixes, because my attempt to isolate the code failed to reproduce the problem.

Using go version 1.24.1 and clickhouse-go v2.34.0, I'm running into a problem inserting rows to CH (24.8.5.1) when an Array(JSON) column is an empty slice.

Given a column:

`events` Array(JSON)

And a type:

type Event struct {
    ... some JSON annotated fields ...
}

I can insert rows (using PrepareBatch and Append), using type []Event, that are interpreted correctly as long as one or more Events are populated.

But if the slice is empty, I get code: 117, message: Invalid version for Object structure serialization.

I've tried working around it by returning prerendered JSON (when the source data is empty), by creating a custom "database/sql" serializer, and a couple of other investigative steps. If I emit the string or raw [], it will appear in CH as ['{}', '{}'] seemingly creating an empty element at each character index, because if I tried to emit []::JSON I got eight such empties.

Finally, I tried creating a separate go project to isolate this call and simply emit rows in the expected format (using type []Event) and these get inserted properly to CH whether empty or not.

The only difference I can see is that my test project defines Event in main.go while my failing implementation defines them in a clickhouseexporter module.

I'm relatively new to go, but I'd appreciate any thoughts on what I should check for next.