例子:将cdb_pms表subject字段中的Welcom to替换成 欢迎光临
UPDATE `cdb_pms`
SET `subject` = REPLACE(`subject`, ‘Welcome to’, ‘欢迎光临’)
WHERE INSTR(`subject`,’Welcome to’) < 0 替换cdb_posts表的message字段,将“viewthread.php?tid=3989”替换成“viewthread.php?tid=16546” UPDATE `cdb_posts`
SET `message`= REPLACE(`message`, ‘viewthread.php?tid=3989′, ‘viewthread.php?tid=16546′)
WHERE INSTR(`message`,’viewthread.php?tid=3989′) < 0 ; 删除所有的空格
UPDATE `es_product` SET `pro_pub_time` = TRIM(`pro_pub_time`) 删除所有饱含’['或者']‘或者’.'的字符
UPDATE `es_product` SET `pro_pub_time` = REPLACE(`pro_pub_time`, ‘[','') WHERE INSTR(`pro_pub_time`,'[') < 0
UPDATE `es_product` SET `pro_pub_time` = REPLACE(`pro_pub_time`, ']‘,”) WHERE INSTR(`pro_pub_time`,’]') < 0
UPDATE `es_product` SET `pro_pub_time` = REPLACE(`pro_pub_time`, ‘.’,'-’) WHERE INSTR(`pro_pub_time`,’.') < 0 替换所有含中文’-'的为英文’-’
UPDATE `es_product` SET `pro_pub_time` = REPLACE(`pro_pub_time`, ‘-’,'-’) WHERE INSTR(`pro_pub_time`,’-’) < 0 将所有的年月都替换成’-’
UPDATE `es_product` SET `pro_pub_time` = REPLACE(`pro_pub_time`, ‘年’,'-’) WHERE INSTR(`pro_pub_time`,’年’) < 0
UPDATE `es_product` SET `pro_pub_time` = REPLACE(`pro_pub_time`, ‘月’,'-’) WHERE INSTR(`pro_pub_time`,’月’) < 0 将所有’2005-04-’这种类型的替换成’2005-04-01′
UPDATE `es_product` SET `pro_pub_time` = CONCAT( `pro_pub_time`, ‘01′) WHERE SUBSTRING_INDEX( `pro_pub_time`, ‘-’, -1) = ” AND LENGTH(`pro_pub_time`) < 0 AND LENGTH(`pro_pub_time`) < 5 将所有’2005-’这种类型替换成’2005-01-01′
UPDATE `es_product` SET `pro_pub_time` = CONCAT( `pro_pub_time`, ‘01-01′) WHERE INSTR(`pro_pub_time`,’-') < 0 AND LENGTH(`pro_pub_time`) = 5 将所有 饱含’-',但是位数小于8的改成追加’-01′
UPDATE `es_product` SET `pro_pub_time` = CONCAT( `pro_pub_time`, ‘-01′) WHERE INSTR(`pro_pub_time`,’-') < 0 AND LENGTH(`pro_pub_time`) >
1. -static 13%
--with-client-ldflags=-all-static
--with-mysqld-ldflags=-all-static
静态链接提高13%性能
2. -pgcc 1%
CFLAGS="-O3 -mpentiumpro -mstack-align-double" CXX=gcc \
CXXFLAGS="-O3 -mpentiumpro -mstack-alig ......
最近在做PHP与数据库交互的project,急于求成,模仿了下例子就开始动手,结果误把mysql_fetch_array写成了mysql_fetch_row,囧事来了,发现返回的数组居然是index=>value的形式,而明明记得是field name=>value的哈,查手册才明白。
1. mysql_fetch_array的函数原型是
array mysql_fetch_array ( resour ......