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sql語言基本語句介紹(編輯修改稿)

2025-10-19 07:23 本頁面
 

【文章內(nèi)容簡介】 te from student where sal=2000。刪除表中的數(shù)據(jù)Truncate table student。刪除表中的所有記錄,表結構還在,無法找回刪除的記錄,速度快Select ename,sal,job from empSelect sal*13+nvl(m,0)*13 “年工資”,ename from empSelect ename,sal from emp where sal=2000 and salSelect distinct ename,deptno from emp。取消重復行Select * from emp where sal(select avg(sal)from emp):%:任意0到多個字符,_:表示任意單個字符Select ename,sal from emp where ename like ?s%?Select ename,sal from emp where ename like ?_s%?:Select * from emp where empno in(7844,7566)Select * from emp where mgr is null by的使用Select * from emp order by deptno asc,sal desc,hiredate desc。排序默認是asc by用于對查詢結果進行分組統(tǒng)計。Having用于限制分組顯示結果。Select avg(sal),deptno from empgroup by deptnohaving avg(sal)1)先創(chuàng)建一個簡單的表:Create table mytest(name varchar2(30),password varchar2(30))2)創(chuàng)建過程:過程1:create procedure sp_pro1 isbegininsert into mytest(?EE?,?m1234?)。end。過程2:create or replace procedure sp_pro2 isbegindelete from mytest where name=?EE?。end。select * from rh_blood where userid=39。K99999826439。 and f_datetime_device between TO_DATE(39。20140101 00:00:0139。,39。yyyymmdd hh24:mi:ss39。)andTO_DATE(39。20140131 23:23:5939。,39。yyyymmdd hh24:mi:ss39。)。第三篇:幾個簡單的基本的sql語句幾個簡單的基本的sql語句(1)數(shù)據(jù)記錄篩選:sql=“select * from 數(shù)據(jù)表 where 字段名=字段值 order by 字段名[desc]”sql=“select * from 數(shù)據(jù)表 where 字段名 like 39。%字段值%39。 order by 字段名 [desc]”sql=“select top 10 * from 數(shù)據(jù)表 where 字段名 order by 字段名[desc]”sql=“select * from 數(shù)據(jù)表 where 字段名 in(39。值139。,39。值239。,39。值339。)”sql=“select * from 數(shù)據(jù)表 where 字段名 between 值1 and 值2”(2)更新數(shù)據(jù)記錄:sql=“update 數(shù)據(jù)表 set 字段名=字段值 where 條件表達式”sql=“update 數(shù)據(jù)表 set 字段1=值1,字段2=值2 …… 字段n=值n where 條件表達式”(3)刪除數(shù)據(jù)記錄:sql=“delete from 數(shù)據(jù)表 where 條件表達式”sql=“delete from 數(shù)據(jù)表”(將數(shù)據(jù)表所有記錄刪除)(4)添加數(shù)據(jù)記錄:sql=“insert into 數(shù)據(jù)表(字段1,字段2,字段3 …)values(值1,值2
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