oracle sql中decode,sql server中类似oracle中decode功能的函数 | 学步园

SQL Server 2008中的写法：

select t.PROJECTNAME,

t.BUILDCONTENTSCALE,

CASE t.PROJECTLEVEL

WHEN '0' THEN '国家重点'

WHEN '1' THEN '省重点'

WHEN '2' THEN '市重点'

WHEN '3' THEN '区/县重点'

END AS PROJECTLEVEL,

t.TOTALINVESTMENT,

t.PROGRESSCONTENT,

t.BUILDCOMPANY,

t.CONTACTWAY,

t.DUTYDEPT,

t.REMARK

from t_iipms_applayprojects t

where t.projecttype = '1'

and t.isvoided = '0';

Oracle 10g中的写法：

select t.PROJECTNAME,

t.BUILDCONTENTSCALE,

decode(t.PROJECTLEVEL,

'0',

'国家重点',

'1',

'省重点',

'2',

'市重点',

'3',

'区/县重点') as PROJECTLEVEL,

t.TOTALINVESTMENT,

t.PROGRESSCONTENT,

t.BUILDCOMPANY,

t.CONTACTWAY,

t.DUTYDEPT,

t.REMARK

from t_iipms_applayprojects t

where t.projecttype = '1'

and t.isvoided = '0';

细节对比看效果很明显：SQL Server 2008中

CASE t.PROJECTLEVEL

WHEN '0' THEN '国家重点'

WHEN '1' THEN '省重点'

WHEN '2' THEN '市重点'

WHEN '3' THEN '区/县重点'

END AS PROJECTLEVEL

Oracle 10g中decode(t.PROJECTLEVEL,

'0',

'国家重点',

'1',

'省重点',

'2',

'市重点',

'3',

'区/县重点') as PROJECTLEVEL