This page provides information about segment compilation for a query.
| Name | Type |
|---|---|
| stream | int2 |
| segment | int2 |
| start | timestamp |
| end | timestamp |
| caching | varchar |
| duration | interval |
The stream ordinal. A query is composed of streams, which execute serially. Stream numbers begin at 0, execute in numeric order, and reset to 0 for each query (so are unique on a per-query basis).
The segment ordinal. A stream is composed of segments, which execute concurrently. Segment numbers begin at 0 but do not reset to 0 per stream, and so are unique, on a per-query basis.
Compilation start time.
Compilation end time.
| value | region | meaning |
|---|---|---|
| compiled | without off-load | leader node compiled the segment |
| compiled | with off-load | off-load system compiled, or retrieved from global segment cache |
| cached | both | retrieved from leader node segment cache |
Note a Redshift cluster from its own system tables has no idea which region it is in; it’s down to you to know, and interpret this column accordingly.
Compilation duration.