Doris always delays the execution of expressions as possible as it can, so as the expansion of constant expression. Given below SQL:
```sql
select i from (select 'abc' as i, sum(birth) as j from subquerytest2) as tmp
```
The aggregation would be eliminated, since its output is not required by the outer block, but the expasion for constant expression would be done in the final result expr, and since aggreagete output has been eliminate, the expasion would actually do nothing, and finally cause a empty results.
To fix this, we materialize the results expr in the inner block for such SQL, it may affect performance, but better than let system produce a mistaken result.
1.Compatible with the old optimizer, the sort and limit in the subquery will not take effect, just delete it directly.
```
select * from sub_query_correlated_subquery1 where sub_query_correlated_subquery1.k1 > (select sum(sub_query_correlated_subquery3.k3) a from sub_query_correlated_subquery3 where sub_query_correlated_subquery3.v2 = sub_query_correlated_subquery1.k2 order by a limit 1);
```
2.Adjust the unnesting position of the subquery to ensure that the conjunct in the filter has been optimized, and then unnesting
Support:
```
SELECT DISTINCT k1 FROM sub_query_correlated_subquery1 i1 WHERE ((SELECT count(*) FROM sub_query_correlated_subquery1 WHERE ((k1 = i1.k1) AND (k2 = 2)) or ((k1 = i1.k1) AND (k2 = 1)) ) > 0);
```
The reason why the above can be supported is that conjunction will be performed, which can be converted into the following
```
SELECT DISTINCT k1 FROM sub_query_correlated_subquery1 i1 WHERE ((SELECT count(*) FROM sub_query_correlated_subquery1 WHERE ((k1 = i1.k1) AND (k2 = 2 or k2 = 1)) ) > 0);
```
Not Support:
```
SELECT DISTINCT k1 FROM sub_query_correlated_subquery1 i1 WHERE ((SELECT count(*) FROM sub_query_correlated_subquery1 WHERE ((k1 = i1.k1) AND (k2 = 2)) or ((k2 = i1.k1) AND (k2 = 1)) ) > 0);
```
1. When mapping column from external datasource, use date/datetimev2 as default type
2. check `is_cancelled` when read data, to avoid endless loop after query is cancelled
1. use one rule to bind slot and function and do type coercion to fix type and nullable error
a. SUM(a1 + AVG(a2)) when a1 and a2 are TINYINT. Before, the return type was SMALLINT, after this PR will return the right type - DOUBLE.
2. fix runtime filter gnerator bugs - bind runtime filter on wrong join conjuncts.
The performance of ClickBench Q30 is affected by batch_size:
| batch_size | 1024 | 4096 | 20480 |
| -- | -- | -- | -- |
| Q30 query time | 2.27 | 1.08 | 0.62 |
Because aggregation operator will create a new result block for each batch block, and Q30 has 90 columns, which is time-consuming. Larger batch_size will decrease the number of aggregation blocks, so the larger batch_size will improve performance.
Doris internal reader will read at least 4064 rows even if batch_size < 4064, so this PR keep the process of reading external table the same as internal table.
Support set skip line number for stream load to load csv file.
Usage `-H skip_lines:number`:
```
curl --location-trusted -u root: -T test.csv -H skip_lines:5 -XPUT http://127.0.0.1:8030/api/testDb/testTbl/_stream_load
```
Skip line number also can be used in mysql load as below:
```sql
LOAD DATA
LOCAL
INFILE '${mysql_load_skip_lines}'
INTO TABLE ${tableName}
COLUMNS TERMINATED BY ','
IGNORE 2 LINES
PROPERTIES ("auth" = "root:");
```
Support master and follow change in multi fe for mtmv
This PR fixes following issues:
1. Start the mtmv only in master node, if master change to follower, it will stop the scheduler.
2. Fix a double meta write here
3. Rename some edit log function and variables
4. If a mv both have PeriodicalJob and immediate job and PeriodicalJob will be trigger right now, scheduler will ignore the immediate job.
5. Fix expired time bugs, and make sure it will be clean among all the fes.
6. cleanerScheduler interval from 1 day to 1 minute.
forbidden to_quantile_state temporary to avoid core dump. waiting for [Feature] support QuantileState in vectorized engine #15868 get the ball rolling on implementation.
If sql in create view has more than one count distinct, and write column name explicitly.
We will generate sql contains function multi_count_distinct.
It cannot be analyzed and all query containing this view will fail.
BufferControlBlock may block all fragment handle threads leads to be out of work
modify include:
BufferControlBlock cancel after max timeout
StmtExcutor notify be to cancel the fragment when unexcepted occur
more details see issue #16203
