SQL之条件查询(高级数据过滤)
1、组合WHERE子句
1.1、AND操作符
1 select 2 col_name 3 from 4 table_name 5 where 6 col_name = 'str' 7 and 8 col_name2 = 'str';
1.2、OR操作符
1 select 2 col_name 3 from 4 table_name 5 where 6 col_name = 'str' 7 or 8 col_name2 = 'str';
2、IN操作符
1 select 2 col_name 3 from 4 table_name 5 where 6 col_name 7 in 8 ("str", "str");
3、NOT操作符
where子句中的NOT操作符有且只有一个功能,就是否定其后所跟的任何条件
1 select 2 col_name 3 from 4 table_name 5 where 6 not 7 col_name = "str";