MySql表按分割字符串的值排序

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我需要表如下结果

RAJ1 RAJ2 ARUN MUTHU 
----------------------- 
86  74 45 null 
74  86 45 null 
null 74 45 86

我不知道从哪里开始通过对程序或通过正常的查询来实现这一点。

来源

2011-12-24 arun kumar non ascii

将每个列联合成一个长列表，将名称，值拆分为2列，然后在名称上进行转义。由于字符串操作，性能会很慢，但是当我们有非规格化数据时会发生这种情况。 – xQbert 2011-12-24 12:42:24

SELECT 
    COALESCE(
    IF(LEFT(subj1,4)='RAJ1', SUBSTRING(subj1,6), NULL), 
    IF(LEFT(subj2,4)='RAJ1', SUBSTRING(subj2,6), NULL), 
    IF(LEFT(subj3,4)='RAJ1', SUBSTRING(subj3,6), NULL)) as RAJ1, 
    COALESCE(
    IF(LEFT(subj1,4)='RAJ2', SUBSTRING(subj1,6), NULL), 
    IF(LEFT(subj2,4)='RAJ2', SUBSTRING(subj2,6), NULL), 
    IF(LEFT(subj3,4)='RAJ2', SUBSTRING(subj3,6), NULL)) as RAJ2, 
    COALESCE(
    IF(LEFT(subj1,4)='ARUN', SUBSTRING(subj1,6), NULL), 
    IF(LEFT(subj2,4)='ARUN', SUBSTRING(subj2,6), NULL), 
    IF(LEFT(subj3,4)='ARUN', SUBSTRING(subj3,6), NULL)) as ARUN, 
    COALESCE(
    IF(LEFT(subj1,5)='MUTHU', SUBSTRING(subj1,7), NULL), 
    IF(LEFT(subj2,5)='MUTHU', SUBSTRING(subj2,7), NULL), 
    IF(LEFT(subj3,5)='MUTHU', SUBSTRING(subj3,7), NULL)) as MUTHU 
FROM thetable;

来源

2011-12-26 10:47:34 newtover

MySql表按分割字符串的值排序

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