Lee Zong Yu

I hereby agree to the terms of the [Singularity Data, Inc. Contributor License Agreement](https://gist.github.com/skyzh/0663682a70b0edde7ae991492f2314cb#file-s9y_cla). ## What's changed and what's your intention? EXISTS implement ## Checklist - [x] I have written...

There is 1 out of 512 query that show this error which previous attempt to run 512 test that doesn,t fail. [error.txt](https://github.com/singularity-data/risingwave/files/9257514/error.txt) it is error occur around here. https://github.com/singularity-data/risingwave/blob/ae0388aeee470bb82b845e14df96220cf51e3d2a/src/frontend/src/expr/subquery.rs#L72 About...