¼¸¸öɾ³ýÖظ´¼Ç¼µÄSQLÓï¾ä
±ÈÈçÏÖÔÚÓÐÒ»ÈËÔ±±í £¨±íÃû£ºpeosons£©
ÈôÏ뽫ÐÕÃû¡¢Éí·ÝÖ¤ºÅ¡¢×¡Ö·ÕâÈý¸ö×Ö¶ÎÍêÈ«ÏàͬµÄ¼Ç¼²éѯ³öÀ´
select p1.* from persons p1,persons p2 where p1.id<>p2.id and p1.cardid = p2.cardid and p1.pname = p2.pname and p1.address = p2.address
¿ÉÒÔʵÏÖÉÏÊöЧ¹û£®
¼¸¸öɾ³ýÖظ´¼Ç¼µÄSQLÓï¾ä
1.ÓÃrowid·½·¨
2.ÓÃgroup by·½·¨
3.ÓÃdistinct·½·¨
1¡£ÓÃrowid·½·¨
¾Ý¾Ýoracle´øµÄrowidÊôÐÔ£¬½øÐÐÅжϣ¬ÊÇ·ñ´æÔÚÖظ´,Óï¾äÈçÏ£º
²éÊý¾Ý:
select * from table1 a where rowid !=(select max(rowid)
from table1 b where a.name1=b.name1 and a.name2=b.name2......)
ɾÊý¾Ý£º
delete from table1 a where rowid !=(select max(rowid)
from table1 b where a.name1=b.name1 and a.name2=b.name2......)
2.group by·½·¨
²éÊý¾Ý:
¡¡¡¡select count(num), max(name) from student --ÁгöÖظ´µÄ¼Ç¼Êý£¬²¢ÁгöËûµÄnameÊôÐÔ
¡¡¡¡group by num
¡¡¡¡having count(num) >1 --°´num·Ö×éºóÕÒ³ö±íÖÐnumÁÐÖظ´£¬¼´³öÏÖ´ÎÊý´óÓÚÒ»´Î
ɾÊý¾Ý£º
¡¡¡¡delete from student
¡¡¡¡group by num
¡¡¡¡having count(num) >1
¡¡¡¡ÕâÑùµÄ»°¾Í°ÑËùÓÐÖظ´µÄ¶¼É¾³ýÁË¡£
3.ÓÃdistinct·½·¨ -¶ÔÓÚСµÄ±í±È½ÏÓÐÓÃ
create table table_new as select distinct * from table1 minux
truncate table table1;
insert into table1 select * from table_new;
²éѯ¼°É¾³ýÖظ´¼Ç¼µÄ·½·¨´óÈ«
1¡¢²éÕÒ±íÖжàÓàµÄÖظ´¼Ç¼£¬Öظ´¼Ç¼ÊǸù¾Ýµ¥¸ö×ֶΣ¨peopleId£©À´ÅжÏ
select * from people
where peopleId in (select peopleId from people group by peopleId having count(peopleId) > 1)
2¡¢É¾³ý±íÖжàÓàµÄÖظ´¼Ç¼£¬Öظ´¼Ç¼ÊǸù¾Ýµ¥¸ö×ֶΣ¨peopleId£©À´Åжϣ¬Ö»ÁôÓÐrowid×îСµÄ¼Ç¼
delete from people
where peopleId
Ïà¹ØÎĵµ£º
ÎÒÃÇÒª½¨Á¢¶à¼¶¹Øϵ£¬Ê×ÏÈÐèÒªÁ½¸ö±í.
µÚÒ»¸ö±í±íʾֱÊô½á¹¹£¬±ÈÈç˵ÎÒÃǹ«Ë¾ÓÐÒ»¸ö²¿ÃÅ¡£¶øÕâ¸ö²¿ÃÅÏ»¹ÓÐ3¸öС×飬ÄÇô3¸öС×éÊôÓÚÕâ¸ö²¿ÃÅ.µÚ¶þ¸ö±í±íʾ¶à²ã½á¹¹,¾ÍÏóµÚÒ»±íÀïÃæËù±íʾµÄ£¬ÕâÈý¸öС×éͬʱ»¹ÊôÓÚ¹«Ë¾.¶øÕâ¸ö¹«Ë¾Í¬Ê±ÊôÓÚÕâ3¸öС×éµÄ¸¸¼¶µÄ¸¸¼¶µÄ²¿ÃÅ¡£¼ÙÈçÎÒ ......
¶øÕâһƪÖУ¬ÎÒÃǾÍΧÈÆSQLÓÅ»¯À´¿ªÊ¼Õâ´Î½²½â£¬ÎªÊ²Ã´µÚÒ»½²ÒªËµSQLÓÅ»¯£¿ÒòΪÎÒÈÏΪÕâÊdzÌÐòÔ±µÄ»ù±¾¹¦£¬¶øÇÒÒ²ÊÇÎÒÃDZØÐëҪȥÕÆÎյģ¬ËäÈ»ÄãдµÄ SQLÓï¾äÄÜÍê³ÉÏàÓ¦µÄ¹¦ÄÜ£¬µ«ÊÇÄãÊÇ·ñ¿¼ÂǹýÕâЩÓï¾äÅöµ½º£Á¿Êý¾Ý»òÕß±©Á¦·ÃÎÊʱ»á²»»á´øÀ´Ð§ÂʵĴó·ù¶ÈµÄ¼õÂý£¿Ò²ÐíºÜ¶à³ÌÐòÔ±ºÍÎÒÒ»ÑùÔÚÅöµ½ÏµÍ³ÏìÓ¦Ê ......
You can user PL SQL Developer in Ubuntu like in Windows:
1.download PL/SQL Developer for linux;
2.Install JDK berfore the next;
3.install the PL/SQL Developer;
4.goto the $PL/SQL Developer,run sh sqldeverloper.sh;
5.type the $JDK;
6.then the PL/SQL Developer will startup. ......
ÏÂÁÐÓï¾ä²¿·ÖÊÇMssqlÓï¾ä£¬²»¿ÉÒÔÔÚaccessÖÐʹÓá£
¡¡¡¡SQL·ÖÀࣺ
¡¡¡¡DDL—Êý¾Ý¶¨ÒåÓïÑÔ(CREATE£¬ALTER£¬DROP£¬DECLARE)
¡¡¡¡DML—Êý¾Ý²Ù×ÝÓïÑÔ(SELECT£¬DELETE£¬UPDATE£¬INSERT)
¡¡¡¡DCL—Êý¾Ý¿ØÖÆÓïÑÔ(GRANT£¬REVOKE£¬COMMIT£¬ROLLBACK)
¡¡¡¡Ê×ÏÈ,¼òÒª½éÉÜ»ù´¡Óï¾ä£º
¡¡¡¡1¡¢ËµÃ÷£º´´½¨Êý¾Ý¿â
......