now-3h, that change automatically based on your time, or absolute times, like
Monday at 3pm. The datetime picker (and the Scroll to field) also accept unix timestamps and ISO8601 strings, making it extremely straightforward to copy datetimes from your other sources, like error reporting.
jsoncolumn, and you need to parse out the individual attributes out, if you want to select and query them. Luckily, it's very easy to do so, using native functions from ClickHouse!
JSONExtractStringfunction and we alias the result as
level, which makes it very easy to query with the attribute further. There are various JSON accessors like
JSONExtractString, here's the full list of functions for working with JSON.