有时候需要对mysql中的内容进行部分替换,那么可以参考下面的文章。
将cdb_pms表subject字段中的Welcom to替换成 欢迎光临
代码如下:
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”
代码如下:
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
代码如下:
UPDATE `es_product` SET `pro_pub_time` = TRIM(`pro_pub_time`)
删除所有饱含'['或者']'或者'.'的字符
代码如下:
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'-'
代码如下:
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'-'
代码如下:
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'
代码如下:
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'
代码如下:
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'
代码如下:
UPDATE `es_product` SET `pro_pub_time` = CONCAT( `pro_pub_time`, '-01') WHERE INSTR(`pro_pub_time`,'-') > 0 AND LENGTH(`pro_pub_time`)
将所有'2005'这样的改成'2005-01-01'
代码如下:
UPDATE `es_product` SET `pro_pub_time` = CONCAT(`pro_pub_time`,'-01-01') WHERE INSTR(`pro_pub_time`,'-') = 0 AND LENGTH(`pro_pub_time`) = 4
最后将所有'2005-01-01'格式化成'2005年01月'
代码如下:
UPDATE `es_product` SET `pro_pub_time` = DATE_FORMAT(`pro_pub_time`,'%Y年%m月') WHERE INSTR(`pro_pub_time`,'-') > 0

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