ÀûÓÃMySQLµÄÒ»¸öÌØÐÔʵÏÖMySQL²éѯ½á¹ûµÄ·ÖÒ³ÏÔʾ
ÔÚmysqlÖÐÀûÓÃselectÓï¾äµÄÒ»¸öÌØÐԾͿÉÒԺܷ½±ãµØÊµÏÖ²éѯ½á¹ûµÄ·ÖÒ³£¬selectÓï¾äµÄÓï·¨£º
SELECT [STRAIGHT_JOIN] [SQL_SMALL_RESULT] [SQL_BIG_RESULT] [HIGH_PRIORITY]
[DISTINCT | DISTINCTROW | ALL]
select_expression,...
[INTO OUTFILE 'file_name' export_options]
[from table_references
[WHERE where_definition]
[GROUP BY col_name,...]
[HAVING where_definition]
[ORDER BY {unsigned_integer | col_name | formula} [ASC | DESC] ,...]
[LIMIT [offset,] rows]
[PROCEDURE procedure_name] ]
LIMIT×Ó¾ä¿ÉÒÔÓÃÀ´ÏÞÖÆÓÉSELECTÓï¾ä·µ»Ø¹ýÀ´µÄÊý¾ÝÊýÁ¿£¬ËüÓÐÒ»¸ö»òÁ½¸ö²ÎÊý£¬Èç¹û¸ø³öÁ½¸ö²ÎÊý£¬
µÚÒ»¸ö²ÎÊýÖ¸¶¨·µ»ØµÄµÚÒ»ÐÐÔÚËùÓÐÊý¾ÝÖеÄλÖ㬴Ó0¿ªÊ¼£¨×¢Òâ²»ÊÇ1£©£¬µÚ¶þ¸ö²ÎÊýÖ¸¶¨×î¶à·µ»ØÐÐ
Êý¡£ÀýÈ磺
select * from table LIMIT 5,10; #·µ»ØµÚ6-15ÐÐÊý¾Ý
select * from table LIMIT 5; #·µ»ØÇ°5ÐÐ
select * from table LIMIT 0,5; #·µ»ØÇ°5ÐÐ
Ïà¹ØÎĵµ£º
Ò»¡¢¸ÅÊö
¡¡¡¡Ê¼þµ÷¶ÈÆ÷ÊÇÔÚ MySQL 5.1 ÖÐÐÂÔöµÄÁíÒ»¸öÌØÉ«¹¦ÄÜ£¬¿ÉÒÔ×÷Ϊ¶¨Ê±ÈÎÎñµ÷¶ÈÆ÷£¬È¡´ú²¿·ÖÔÏÈÖ»ÄÜÓòÙ×÷ϵͳÈÎÎñµ÷¶ÈÆ÷²ÅÄÜÍê³ÉµÄ¶¨Ê±¹¦>ÄÜ¡£ÀýÈ磬Linux ÖÐµÄ crontabe Ö»Äܾ«È·µ½Ã¿·ÖÖÓÖ´ÐÐÒ»´Î£¬¶ø MySQL µÄʼþµ÷¶ÈÆ÷Ôò¿ÉÒÔʵÏÖÿÃëÖÓÖ´ÐÐÒ»¸öÈÎÎñ£¬ÕâÔÚһЩ¶ÔʵʱÐÔÒª>Çó½Ï¸ßµÄ»·¾³Ï¾ͷdz£ÊµÓÃÁ ......
Óöµ½Ò»¸öÎÊÌâÊÇÔÚMySQLÃüÁîÐвåÈëÖÐÎÄÊý¾Ý»òÕß²éѯÖÐÎÄÊý¾Ýʱ³öÏÖÂÒÂ룬»òÕßÏÔʾ²»¶Ô¡£
ÔÚÃüÁîÐÐÊäÈë:show variables like ‘character_set_%’;
²é¿´µ±Ç°ÅäÖõıàÂ룻
ÔÚÃüÁîÐÐÊäÈë :set names utf8;
ÔòµÈͬÓÚ
set character_set_client=utf8;
set character_set_results ......
½ñÌìÖÕÓÚÕÒµ½×Ô¼ºµ÷ÊÔÉÐѧÌÃshoppingÏîĿʱµÄÎÊÌâËùÔÚÁË£¬Í¨¹ý²é×ÊÁÏ£¬¶ÔmyeclipseºÍtomcatµÄ²¿ÊðÓÖÓÐÁ˸üÉîÒ»¸ö²ã´ÎµÄÁ˽⣬³ÌÐòµ÷ͨÁË£¬ÐË·ÜÁËÒ»ÏÂÏ£¬¹þ¹þ¡£¡£
È¥ºǫ́Ìí¼ÓÊý¾Ý·¢ÏÖ´ÓmysqlÖжÁ³öµÄÖÐÎÄÈ«²¿ÏÖʵΪ¿É°®µÄÎʺţ¬ÕâϺÃÁË£¬ÎÒÐÄÀïÒ²²úÉúÎʺŠ......
MySQLµÄ×Ö·û¼¯ÎÊÌâ¡£WindowsÏ¿Éͨ¹ýÐÞ¸Ämy.iniÄÚµÄ
CODE:
# CLIENT SECTION
[mysql]
default-character-set=utf8
#
SERVER SECTION
[mysqld]
default-character-set=utf8
Õâ
Á½¸ö×Ö¶ÎÀ´¸ü¸ÄÊý¾Ý¿â
µÄ
ĬÈÏ×Ö·û¼¯¡£µÚÒ»¸öÊǿͻ§¶ËĬÈϵÄ×Ö·û¼¯£¬µÚ¶þ¸öÊÇ·þÎñÆ÷¶ËĬÈϵÄ×Ö·û¼¯¡£¼ÙÉèÎÒÃǰÑÁ½¸ö¶¼ÉèΪutf8£¬È»ºó ......
ÎÒÓõÄÊÇmysql5.0£¬
ÎÒ³ÌÐòÖÐÓõ½ÁËÒ»¾äsqlÊÇ
SQL code
select count(DISTINCT id) from Policyinfo p where p.filename not in
(select p2.filename from Policyreadinfo p2 where p2.reader='test')
µ«ÊÇÿ´ÎÔÚ³ÌÐòÖÐÿ´ÎÖ´ÐÐÕâ¾äsqlÊ±ÍøÒ³¾ÍÌØÂý£¬Òª10¶àÃ룬¶øÕâ2¸ö±íµÄ¼Ç¼ÐÐÊýÒ²¾Í1000¶à¶øÒÑ£¬ÎÒ°ÑÕâ¾äsqlµ¥¶ÀÄ ......