Fix the query plan of count(*) META_SCAN #65886
Description
Steps to reproduce the behavior (Required)
Normal META_SCAN return a correct count:
MySQL [email protected]:d1> explain costs SELECT
-> cast(COUNT(k1) AS BIGINT)
-> FROM
-> `test_array_collection_size1` partitions (`test_array_collection_size1`) [_META_];
| 0:MetaScan |
| Table: test_array_collection_size1 |
| <id 6> : count_k1 |
| Partitions: [test_array_collection_size1] |
| cardinality: 1 |
| column statistics: |
| * count_k1-->[1.0, 1.0, 0.0, 4.0, 1.0] ESTIMATE |
count(*) return 0:
MySQL [email protected]:d1> explain costs SELECT
-> cast(COUNT(*) AS BIGINT)
-> FROM
-> `test_array_collection_size1` partitions (`test_array_collection_size1`) [_META_];
1:Project |
| | output columns: |
| | 7 <-> 1 |
| | cardinality: 1 |
| | column statistics: |
| | * auto_fill_col-->[1.0, 1.0, 0.0, 1.0, 1.0] ESTIMATE |
| | |
| 0:MetaScan |
| Table: test_array_collection_size1 |
| Partitions: [test_array_collection_size1] |
| cardinality: 1 |
| column statistics: |
| * k1-->[1.0, 1.0, 0.0, 4.0, 1.0] ESTIMATE |
| * p_date-->[1.6725024E9, 1.6725024E9, 0.0, 4.0, 1.0] ESTIMATE |
| * int_arr-->[-Infinity, Infinity, 0.0, 12.0, 1.0] COS: 3.0 ESTIMATE |
| * str_arr-->[-Infinity, Infinity, 0.0, 48.0, 1.0] COS: 3.0 ESTIMATE |
+--------------------------------------------------------------------------------------------------+
To conclude, count(*) [_META_SCAN] cannot choose a correct column, leading to incorrect query result.
Expected behavior (Required)
Correct count.
Real behavior (Required)
the count is 0.
StarRocks version (Required)
- You can get the StarRocks version by executing SQL
select current_version() - branch main 20251124