[Feature](Nereids) Add hint to enable pre-aggregation when scan OLAP table.

[wangshuo128]

Proposed changes

This pr added support for the pre-aggregation hint. Users could use /*+PREAGGOPEN*/ to enable pre-preaggregation for OLAP table.
For example:
Let's say we have an aggregate-keys table t (k1 int, k2 int, v1 int sum, v2 int sum). Pre-aggregation could be enabled by query with a hint: select k1, v1 from t /*+PREAGGOPEN*/.

Checklist(Required)

1. Does it affect the original behavior:
   • Yes
   • No
   • I don't know
2. Has unit tests been added:
   • Yes
   • No
   • No Need
3. Has document been added or modified:
   • Yes
   • No
   • No Need
4. Does it need to update dependencies:
   • Yes
   • No
5. Are there any changes that cannot be rolled back:
   • Yes (If Yes, please explain WHY)
   • No

Further comments

If this is a relatively large or complex change, kick off the discussion at dev@doris.apache.org by explaining why you chose the solution you did and what alternatives you considered, etc...

[hello-stephen]

TeamCity pipeline, clickbench performance test result:
the sum of best hot time: 33.78 seconds
load time: 485 seconds
storage size: 17172244183 Bytes
https://doris-community-test-1308700295.cos.ap-hongkong.myqcloud.com/tmp/20230202102840_clickbench_pr_89427.html

[morningman]

Why we need hint to do this? This should be set automatically by optimizer?

[wangshuo128]

Why we need hint to do this? This should be set automatically by optimizer?

This hint is supported by the old planner currently.
AFAIK, people can use this hint when the optimizer can't recognize the query could use pre-aggregation automatically, such as OLAP scan node in joins, subqueries or aggregate functions' input is not a slot reference but complex expressions.
Ideally, pre-aggregation should be set by the optimizer. But this hint leaves a chance for users to enable pre-aggregation for cases that optimizer can't work well.

[morningman]

Why we need hint to do this? This should be set automatically by optimizer?

This hint is supported by the old planner currently. AFAIK, people can use this hint when the optimizer can't recognize the query could use pre-aggregation automatically, such as OLAP scan node in joins, subqueries or aggregate functions' input is not a slot reference but complex expressions. Ideally, pre-aggregation should be set by the optimizer. But this hint leaves a chance for users to enable pre-aggregation for cases that optimizer can't work well.

OK, I see

[github-actions]

PR approved by at least one committer and no changes requested.

[github-actions]

PR approved by anyone and no changes requested.