基于表中值的动态SQL

Question

我需要动态创建SQL，我有一个像这样的表：

Operator  Value
BETWEEN   0 AND 21
BETWEEN   21 AND 50

我需要编写一个将基本执行的查询：

SELECT * FROM tbl
WHERE 22 Operator Value

这应该返回上表的第二行。

Answer 1

您可以尝试一下，尝试一下

if object_id('tempdb..#Test') is not null drop table #Test
create table #Test (Operator nvarchar(20), Value nvarchar(20))

insert into #Test (Operator, Value)
values
('BETWEEN', '0 AND 21'),
('BETWEEN', '21 AND 50')

declare @sql nvarchar(max) = 'SELECT * FROM #Test WHERE 22 '

declare @sqlHelper nvarchar(max) = 
                (select Operator + ' ' + Value
                        + ' and Value = '''+Value+''''
                        from #Test 
                        where 22 <= Cast(RIGHT(Value, 2) as int) and
                              22 >= Cast(LEFT(Value, 2) as int))

select @sql + @sqlHelper 
execute (@sql + @sqlHelper)

extrester： http： //rextester.com/OJTIW53082

执行的查询是： SELECT * FROM #Test WHERE 22 BETWEEN 21 AND 50 and Value = '21 AND 50'

结果：

+----------+-----------+
| Operator |   Value   |
+----------+-----------+
| BETWEEN  | 21 AND 50 |
+----------+-----------+