中國統(tǒng)計(jì)網(wǎng) 2017-05-26 18:25:10 下面就為大家?guī)硪黄猄QL語句快速入門 。個人覺得挺不錯的,學(xué)習(xí)MYSQL數(shù)據(jù)庫還是有點(diǎn)幫助的,給大家做個參考吧。 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啞元表沒有表需要查詢的時候可以用它 select sysdate from dual; select 1*2*3*4*5 from dual; 以上這篇SQL語句快速入門 就是分享給大家的全部內(nèi)容了,希望能啟發(fā)大家的思路,如有更多意見,歡迎下方評論~ End. |
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