Ëæ»úÑ¡ÔñÐеÄSQLÓï¾ä? ORACLE SQLSERVER ECT.
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 Tim
Oracle:
SELECT column from
( SELECT column from table
ORDER BY dbms_random.value )
WHERE rownum = 1
Thanks Mark Murphy
Feel free to post other example, variations, and SQL statements for other database servers in the comments.
Ïà¹ØÎĵµ£º
¼oracleÊý¾Ý¿âʱ³£ÓõIJÙ×÷ÃüÁîÕûÀí
1¡¢su – oracle ²»ÊDZØÐ裬ÊʺÏÓÚûÓÐDBAÃÜÂëʱʹÓ㬿ÉÒÔ²»ÓÃÃÜÂëÀ´½øÈësqlplus½çÃæ¡£
2¡¢sqlplus /nolog »òsqlplus system/manager »ò./sqlplus system/manager@ora9i;
3¡¢SQL>connect / as sysdba ;£¨as sysoper£©»ò
connect internal/oracle AS SYSDBA ;(scott/tiger) ......
ÒÔsystemµÇ¼½øÈ¥Ö®ºó£¬Ö´ÐÐÏÂÃæµÄÃüÁ
SQL> alter user scott account unlock; £¨Íê³É½âËøµÄ²Ù×÷£©
Óû§ÒѸü¸Ä¡£
SQL> alter user scott identified by tiger; £¨ÖØÐ¸øscottÕâ¸öÓû§É趨ÃÜÂ룩
Óû§ÒѸü¸Ä¡£
SQL> conn scott/tiger
ÒÑÁ¬½Ó¡£ ......
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
......
Êý¾Ý¿âµÄÐÔÄܲâÊÔ¿ÉÒÔ°ïÖúÄãÌáǰ֪µÀÄãµÄϵͳµÄ¸ºÔØÄÜÁ¦£¬¿ÉÒÔ°ïÖúÄã¸Ä½øÏµÍ³µÄʵʩ»òÉè¼Æ£¬¿ÉÒÔ°ïÖúÄãÈ·¶¨Ò»Ð©Éè¼ÆºÍ±à³ÌÔÔò. µ«ÊÇ£¬ÕâÀïÃæÒ²ÓÐÏÝÚå. Èç¹û²»Ð¡ÐÄ£¬Äã»á×Ô¼º°Ñ×Ô¼ºÏݽøÈ¥£¬È´×îÖÕ²»Ã÷°×ÊÇʲôÔÒò. ÕâÀÎÒÄÃһλÏÈÉúΪÀý£¬À´¿´¿´ËûÔõô×Ô¼º°Ñ×Ô¼º¸ãºýÍ¿µÄ.
×î½ü, ÏëÆðÔÚ´æ´¢¹ý³ÌÖо¿¾¹ÊÇʹÓÃÁÙʱ±í»¹ÊÇÊ ......