We should introduce a minimum sample size in bytes for COMPUTE STATS TABLESAMPLE. Reasons:
- For small tables sampling does not make sense. Accurate stats can be obtained cheaply without sampling.
- Very small sample sizes mostly do not make sense - some minimum of data is required to get meaningful stats.
I think a 1GB minimum might be a good choice and ideally this minimum sample size would be configurable.
Many other DBMS have stats collection with sampling and in many cases a minimum sample size is required to get any meaningful stats.