Merge pull request #12 from hello-stephen/hello-stephen-patch-6

[chore][ci] add README.md for regression-test

regression-test/README.md

@@ -0,0 +1,51 @@
+<!--
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements.  See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership.  The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License.  You may obtain a copy of the License at
+
+  http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+KIND, either express or implied.  See the License for the
+specific language governing permissions and limitations
+under the License.
+-->
+
+# 新加case注意事项
+
+1. 变量名前要写 def，否则是全局变量，并行跑的 case 的时候可能被其他 case 影响。
+
+    Problematic code:
+    ```
+    ret = ***
+    ```
+    Correct code:
+    ```
+    def ret = ***
+    ```
+2. 尽量不要在 case 中 global 的设置 session variable，也可能会影响其他 case。
+
+    Problematic code:
+    ```
+    sql """set global enable_pipeline_x_engine=true;"""
+    ```
+    Correct code:
+    ```
+    sql """set enable_pipeline_x_engine=true;"""
+    ```
+3. case 中涉及时间相关的，最好固定时间，不要用类似 now() 函数这种动态值，避免过一段时间后 case 就跑不过了。
+
+    Problematic code:
+    ```
+    sql """select count(*) from table where created < now();"""
+    ```
+    Correct code:
+    ```
+    sql """select count(*) from table where created < '2023-11-13';"""
+    ```