Commit Graph

3 Commits

Author SHA1 Message Date
Amos Bird
3be331edeb
Better exception for invalid projection creation 2021-05-31 12:24:09 +08:00
Nikolai Kochetov
95431168c2
Try to enable normal projections. 2021-05-11 18:12:26 +08:00
Amos Bird
264cff6415
Projections
TODO (suggested by Nikolai)

1. Build query plan fro current query (inside storage::read) up to WithMergableState
2. Check, that plan is simple enough: Aggregating - Expression - Filter - ReadFromStorage (or simplier)
3. Check, that filter is the same as filter in projection, and also expression calculates the same aggregation keys as in projection
4. Return WithMergableState if projection applies

3 will be easier to do with ActionsDAG, cause it sees all functions, and dependencies are direct (but it is possible with ExpressionActions also)

Also need to figure out how prewhere works for projections, and
row_filter_policies.

wip
2021-05-11 18:12:23 +08:00