34 System failure
35 Data Missing
36 Unexpected Data Value
21 Facility Not Supported
Kafka acts as a kind of write-ahead log (WAL) that records messages to a persistent store (disk) and allows subscribers to read and apply these changes to their own stores in a system appropriate time-frame.
Terminology:
| SELECT table, | |
| formatReadableSize(sum(bytes)) as size, | |
| min(min_date) as min_date, | |
| max(max_date) as max_date | |
| FROM system.parts | |
| WHERE active | |
| GROUP BY table |