Question

使用SQL Server 2012，我有一个包含多个复选框字段的表，显然值为1或0。我需要拉出任何这些值为1的字段。

所以：

ID      Building            Heavy         Municipal       Industry
101        1                   1              0               1

结果：

ID               Type
101              Building, Heavy, Industry

我不能为我的生活弄清楚语法。

Answer 1

假设数列很少，可以使用IIF 2012+，否则就是

确定起始位置和结束的子串。

select ID, 
    SUBSTRING(
    IIF(Building=1,', Building','') + 
            IIF(Heavy=1,', Heavy','') + 
            IIF(Municipal=1,', Municipal','') + 
            IIF(Industry=1,', Industry','')
            ,3,100)   -- substring to start from pos 3 and ends at position 100 depends on the desired length
           Type
from table

Answer 2

这样做的一种方法是，步骤1.取消表格

SELECT ID, Sub, SubVal
INTO #t2
FROM (SELECT * FROM #t)t
UNPIVOT
(
    SubVal FOR Sub IN (Building,Heavy, Muncipal, Industry)
) as un

步骤2：用于FOR XML PATH，

SELECT DISTINCT ID,
    STUFF((
        SELECT ' , ' + t2.Sub  
        FROM #t2 t2
        WHERE SubVal = 1
        FOR XML PATH('')
    ), 1, 2, '')   AS Type
FROM #t2 ct

Answer 3

您也可以使用CASE语句：

create table test (
    id int,
    building int,
    heavy int,
    municipal int,
    industry int
);
insert into test values (101, 1, 1, 0, 1);

with data as (
    select id,
        case when building = 1 then 'Building,' else '' end +
        case when heavy = 1 then 'Heavy,' else '' end +
        case when municipal = 1 then 'Municipal,' else '' end +
        case when industry = 1 then 'Industry,' else '' end as fld
    from test
)
select id, left(fld, len(fld)-1) as fld from data;

示例：http://rextester.com/CKGES46149

结果：

id  fld
101 Building,Heavy,Industry

如果需要逗号之后的空格，请添加一个稍微修改，如下所示：

with data as (
    select id,
        rtrim(
        case when building = 1 then 'Building, ' else '' end +
        case when heavy = 1 then 'Heavy, ' else '' end +
        case when municipal = 1 then 'Municipal, ' else '' end +
        case when industry = 1 then 'Industry, ' else '' end
        ) as fld
    from test
)
select id, left(fld, len(fld)-1) as fld from data;

结果：

id  fld
101 Building, Heavy, Industry

示例：http://rextester.com/OJNEQ98420

逗号从多个sql列分隔列表

3 个答案: