X_ENTITY_SERIES_INVALID
Means
a time series asked for something no bucket can answer
Typical cause
an unknown unit, an on column that is not a timestamp(), a zone that is not IANA, or more buckets than one statement answers
Fix
posts.series({ on: 'createdAt', unit: 'day', timeZone: 'Europe/Berlin', value: 'count' }) — a listed unit, a timestamp() column, an IANA zone, a range under the bucket ceiling