1、最簡單查詢：
select * from car;
2、查詢制定列：
select name oil,powers from car;
3、對查出的列名修改名字：
select name as '車名',oil as '油耗',powers as '動力' from car;
4、按條件查詢：
select name,oil,powers from car where oil = 8.7;
5、多條件查詢：
select name,oil,powers from car where oil = 8.7 or powers = 160;
select name,oil,powers from car where oil = 8.7 and powers = 160;
6、範圍查詢：
select * from car where price>=40 and price <=60;
select * from car where price between 40 and 60;
7、離散查詢：
select * from car where powers = 130 or powers = 150 or powers = 170;
select * from car where powers in (130,150,170);
select * from car where powers not in (130,150,170);
8、模糊查詢：
select * from car where name like '%寶馬%'；
select * from car where name like '_寶馬%'；
9、排序查詢： asc 公升序 desc 降序 order by
select * from car order by oil asc;
select * from car order by brand asc,price desc;
10、去重複查詢： distinct
select distinct brand from car;
11、分頁查詢：
select * from car limit 5,5;
n;m = 5;
limit (n-1)*m,m; 【補充】
12、聚合函式查詢：
count(列名) sum(列名) **g(列名) max(列名) min()
select count(*) from car;
select sum(price) from car;
select **g(price) from car;
select max(price) from car;
select min(price) from car;
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