對于數(shù)據(jù)庫來說多多少少要掌握一點(diǎn)，首先基本的SQL語句要了解。下面來總結(jié)一些入門級別的SQL語句。

create相關(guān)

•show database; 顯示出現(xiàn)有的數(shù)據(jù)庫
•use database_x; 現(xiàn)在要使用數(shù)據(jù)庫database_x
•create table coffee (id int(5) not null,coffee_name varchar(25)); 創(chuàng)建一張表，包含id和coffee_name兩個字段
•alter table coffee add taste varchar(10); 增加新的一列
•insert into coffee (id,coffee_name,taste,rank) value ("1","BlueMountain"，“well”，“5”); 插入數(shù)據(jù)
•show columns from coffee; 查看表結(jié)構(gòu)
•show create table coffee; 查看表信息，包括建表語句
•alter table student rename ss; 改變表名
•alter table ss drop mark; 刪除表ss中mark列
select語句

•select * from coffee where id="1"; 查詢出id=1的所有信息
•select coffee_name from coffee where id="2"; 查詢出id=2的coffee name
•select * from club where id between "1" and "3"; 查詢出id=1到3的條目
•select * from club where id="1" or id="3"; 查詢出id=1和id=3這兩個條目
•select club_name from club where mark>50; 查詢出mark大于50的club
•select club_name from club where mark not between  48 and 50; 查詢mark不在48與50之間的club
•select * from club where id in("1","3","4"); 查詢id=1,3,4的條目
•select * from club where id not in("1","3","4");
•select * from club where name like "M%r"; 通配符%表示任意長度的字符（可以是0，漢字為兩個字符）
•select * from club where name like "M_r"; _表示單個字符
•select * from club where id in("1","3","4") and mark>50; 多重查詢
•select * from club order by mark desc; 按照mark降序排列（desc：降序，usc：升序）
數(shù)量查詢相關(guān)

•select count(*) from club; 查詢club中有多少條記錄
•select count(distinct mark) from club; 不同分?jǐn)?shù)的有多少條記錄
•select sum(mark) from club; 積分總和
•select avg(mark) from club; 平均積分
•select max(mark) from club; 最高積分
•select min(mark) from club; 最低積分
update語句

•update club set mark=mark-8 where id="1"; id=1的俱樂部積分罰8分
delete語句

•delete from club where id="001"; 刪除id=001的俱樂部信息
以上語句都是SQL語句增刪改查最基本的部分，屬于入門級別，一定要掌握。

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