# SQL的基本元素
- **[数据类型](https://support.huaweicloud.com/distributed-ref-v10-gaussdb/gaussdb-08-0510.html)**   
- **[数据类型比较规则](https://support.huaweicloud.com/distributed-ref-v10-gaussdb/gaussdb-08-0511.html)**   
- **[字面量](https://support.huaweicloud.com/distributed-ref-v10-gaussdb/gaussdb-08-0512.html)**   
- **[格式模型](https://support.huaweicloud.com/distributed-ref-v10-gaussdb/gaussdb-08-0513.html)**   
- **[空值](https://support.huaweicloud.com/distributed-ref-v10-gaussdb/gaussdb-08-0514.html)**   
- **[注释](https://support.huaweicloud.com/distributed-ref-v10-gaussdb/gaussdb-08-0515.html)**   
- **[数据库对象](https://support.huaweicloud.com/distributed-ref-v10-gaussdb/gaussdb-08-0516.html)**   
- **[数据库对象名称和限定符](https://support.huaweicloud.com/distributed-ref-v10-gaussdb/gaussdb-08-0517.html)**   
- **[SQL语句中的引用架构对象和部件的语法](https://support.huaweicloud.com/distributed-ref-v10-gaussdb/gaussdb-08-0518.html)**