在学习PostgreSQL的过程中，为了能和mysql区别比较，总结本篇笔记。
比较如下表格：
| 操作 | PostgreSQL | MySQL |
|---|---|---|
| aaaaaaaaa | aaaaaaaaa | aaaaaaaaa |
| aaaaaaaaa | aaaaaaaaa | aaaaaaaaa |
| aaaaaaaaa | aaaaaaaaa | aaaaaaaaa |
| aaaaaaaaa | aaaaaaaaa | aaaaaaaaa |
| aaaaaaaaa | aaaaaaaaa | aaaaaaaaa |
| aaaaaaaaa | aaaaaaaaa | aaaaaaaaa |
| aaaaaaaaa | aaaaaaaaa | aaaaaaaaa |
| aaaaaaaaa | aaaaaaaaa | aaaaaaaaa |
| aaaaaaaaa | aaaaaaaaa | aaaaaaaaa |
| aaaaaaaaa | aaaaaaaaa | aaaaaaaaa |
| aaaaaaaaa | aaaaaaaaa | aaaaaaaaa |
| aaaaaaaaa | aaaaaaaaa | aaaaaaaaa |
| aaaaaaaaa | aaaaaaaaa | aaaaaaaaa |
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