5±¾¾µäSQLµç×ÓÊé
SQL±¦µä
SQL±ØÖª±Ø»áµÚÈý°æ
SQLÈëÞµäµÚËÄ°æ
Sams Teach Yourself SQL in 10 Minutes Third Edition
SQL The Complete Reference
Ïà¹ØÎĵµ£º
ÆÕͨÐÐÁÐת»»
ÎÊÌ⣺¼ÙÉèÓÐÕÅѧÉú³É¼¨±í(tb)ÈçÏÂ:
ÐÕÃû ¿Î³Ì ·ÖÊý
ÕÅÈý ÓïÎÄ 74
ÕÅÈý Êýѧ 83
ÕÅÈý ÎïÀí 93
ÀîËÄ ÓïÎÄ 74
ÀîËÄ Êýѧ 84
ÀîËÄ ÎïÀí 94
Ïë±ä³É(µÃµ½ÈçϽá¹û)£º
ÐÕÃû ÓïÎÄ Êýѧ ÎïÀí
---- ---- ---- ----
ÀîËÄ 74 84 94
ÕÅÈý 74 83 93
-------------------
*/
create table tb(Ð ......
for ACCESS :
update a, b set a.name=b.name1 where a.id=b.id
for SQL Server:
"update a set a.name=b.name1 from a,b where a.id=b.id"
update a set a.status=b.status
from table1 a,table2 b
&nbs ......
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
......
MySQL:
SELECT column from table
ORDER BY RAND()
LIMIT 1
PostgreSQL:
SELECT column from table
ORDER BY RANDOM()
LIMIT 1
Microsoft SQL Server:
SELECT TOP 1 column from table
ORDER BY NEWID()
IBM DB2
SELECT column, RAND() as IDX
from table
ORDER BY IDX FETCH FIRST 1 ROWS ONLY
Thanks Ti ......
#Region " ÃüÃû¿Õ¼ä "
Imports System.Data
Imports System.Data.SqlClient
#End Region
Public Class DBCommon
Implements IDisposable
#Region " ³ÉÔ±±äÁ¿ "
Private conn As SqlConnection
Private cmd As SqlCommand
Private trans As SqlTransaction
#End Region
#Region " ¹¹Ô캯Êý "
......