When the table is empty, SR SQL syntax checker can not infer the type of user defined variable correctly

[zhangyaqi1989]

Steps to reproduce the behavior (Required)

1. CREATE TABLE quickstart.example_table (`pk` BIGINT, `activity` String) DISTRIBUTED BY HASH (`pk`) PROPERTIES("replication_num" = "1");
2. SET @var = (SELECT ARRAY_AGG(activity) FROM quickstart.example_table);
3. SELECT ARRAY_CONTAINS(ARRAY_CONCAT(@var), "a");

Expected behavior (Required)

The SQL should run successfully.

Note that if you insert a row in the table, the SQL will work. Also the below SQL which does not use user defined variable works.

WITH input AS (SELECT ARRAY_AGG(activity) AS activities FROM quickstart.example_table) SELECT ARRAY_CONTAINS(ARRAY_CONCAT(input.activities), "a") FROM input;

Real behavior (Required)

ERROR 1064 (HY000): Getting analyzing error from line 1, column 22 to line 1, column 39. Detail message: 1-th input of array_concat should be an array, rather than varchar.

StarRocks version (Required)

• 3.3