oracleС¼Ç1 5ºÅ

Ò»¡¢          oracle»ù´¡ÖªÊ¶
a¡¢  CRUD²Ù×÷ create read update delete
b¡¢  Êý¾Ý¿â¶ÔÏó
c¡¢  Êý¾Ý¿âÉè¼Æ
d¡¢  Êý¾Ý¿â½á¹¹ÌåϵÓÅ»¯£¨DBA£©
oracleÖдæÔÚËÄÕÅÁ·Ï°±í emp dept slmgad bonus ÕâËÄÕÅ±í£¬»¹ÓÐÒ»ÕÅdual±íÁ·Ï°±í±íÖÐÖ»ÓÐÒ»¸ö×Ö¶ÎÒ»¸öÊý¾Ý¡£
¶þ¡¢          select×Ö¶ÎÖеÄһЩ³£ÓÃ×Ö¶Î
1¡¢  distinct ɾ³ýÖظ´×Ö¶Î
select distinct job from emp;
2¡¢  between ÔÚÖ®¼ä
   select * from emp where sal between 1000 and 2000;
   in ºÍ not inºÍbetween ÓеãÀàËÆ
                  select * from emp where sal in(1000,2000);
         select * from emp where sal not in(1000,2000);
3¡¢  order by ÅÅÐòascÉýÐò£¨Ä¬ÈÏ£© desc½µÐò
   select * from emp order by ename desc,sal;
4¡¢  like×Ö¶ÎÄ£ºýÕÒµ½ not likeÈ¡·ñ
   select * from emp where ename like '%R%'; 
   _±íʾһ¸ö×Öĸ
   select * from emp where ename like '_A%'; ±íʾÒÔAΪµÚÒ»¸ö×ÖĸµÄÐÕÃû
5¡¢              escapeתÒå
              select * from emp where ename like '/_A%' escape '/'; ‘¶Ô/ºóÃæµÄ_’½øÐÐתÒå
6¡¢  union Á¬½Ó
SQL> select job from emp where job='CLERK' union select job from emp where job='SALESMAN';
7¡¢  nulls first ¿ÕÖµÅÅÁзÅÔÚÇ° nulls last
select * from emp order by comm nulls first;
select * from emp order by comm nulls last;
Èý¡¢          º¯Êý
1¡¢×Ö·ûº¯Êý
Upper()×ÖĸСд±ä´óд
select upper('addb') from dual;
                        lower()´ó×Ö×Öĸ±äСд
     &nbs