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下面就為大家?guī)?lái)一篇SQL語(yǔ)句快速入門 。個(gè)人覺(jué)得挺不錯(cuò)的，學(xué)習(xí)MYSQL數(shù)據(jù)庫(kù)還是有點(diǎn)幫助的，給大家做個(gè)參考吧。

Select * from tablename

SQL> select * from employees;

Select select list from tablename

SQL> select employee_id,first_name from employees;

Select distinct … from tablename

SQL> select distinct manager_id from employees;

||連接符使用以及 加減乘除以及括號(hào)的使用

SQL> select employee_id,first_name||'.'||last_name,salary*(1+0.1)/100,manager_id

2 from employees;

+-做正負(fù)號(hào)使用

SQL> select -salary from employees;

<>,>,<,=,!=等比較操作符

SQL> select * from employees where salary >13000;

SQL> select * from employees where salary <13000;

SQL> select * from employees where salary <>13000;

SQL> select * from employees where salary =13000;

In

SQL> select -salary from employees where employee_id in (100,101,102);

SQL> select -salary from employees where employee_id in (select employee_id from employees);

not in

SQL> select -salary from employees where employee_id not in (100,101,102);

Any(比任意一個(gè)都)

select * from employees where employee_id >any(100,101,102);

some 是 SQL-92 標(biāo)準(zhǔn)的 any 的等效物

select * from employees where employee_id >any(100,101,102);

all（比所有的都）

select * from employees where employee_id >all(100,101,102);

between and

select * from employees where employee_id between 100 and 102;

not between and

select * from employees where employee_id not between 100 and 102;

邏輯操作符

And 和 or

select * from employees where employee_id > 100 and employee_id < 1000;

select * from employees where employee_id > 100 or employee_id < 1000;

Order by

Desc

select * from employees where employee_id between 100 and 102 order by employee_id desc;

Asc

select * from employees where employee_id between 100 and 102 order by employee_id asc;

dual啞元表沒(méi)有表需要查詢的時(shí)候可以用它

select sysdate from dual;

select 1*2*3*4*5 from dual;

以上這篇SQL語(yǔ)句快速入門 就是分享給大家的全部?jī)?nèi)容了，希望能啟發(fā)大家的思路，如有更多意見，歡迎下方評(píng)論~

End.