DYNAMIC UNION表

Question

我想创建一个动态表，我不必每月都更新表名。因为我有相同的查询工作（没有变化，但表名称，格式为（dbo.tablename_201705）至（dbo.tablename_201706）等等。所以我创造了这个

DECLARE @TABLE_NAME VARCHAR(20) 
SET @TABLE_NAME ='dbo.GTI_'+left (convert(varchar,dateadd(mm,-3, getdate()-7), 112) ,6) 

DECLARE @GTI_SQL_REPORT VARCHAR(255) 
SET @GTI_SQL_REPORT = 'select*from '+@TABLE_NAME. 

，从这里我丢失我不知道下一步 这里下面是我的查询

Select 
    [CountryID], 
    COUNT([Document name]) as [inputcount], 
    MONTH([Creation Date]) AS [Creation Month], 
    Year([Creation Date]) as [Creation Year] 
from 
    dbo.GTI_201705 
WHERE 
    [doc_type_product_type] not in ('CUST') 
    and [Document_Source] in ('FAX','Original') 
group by 
    [CountryID], 
    MONTH([Creation Date]) , 
    Year([Creation Date]) 
order by 
    [CountryID]; 

这样的想法是创建一个动态表，以便该查询将在每个月初运行。预先感谢您

Answer 1

您近距离了...您只需要设置@GTI_SQL_REPORT到varchar(max)，然后将查询设置为它。 varchar(255)将不足以容纳您的动态字符串。注意底部的print(@GTI_SQL_REPORT)。首先这样做是明智的，所以你会看到你正在执行的SQL。一旦你满意......然后只是评论一下，取消注释EXEC命令。

DECLARE @TABLE_NAME VARCHAR(20) 
SET @TABLE_NAME ='dbo.GTI_'+left (convert(varchar,dateadd(mm,-3, getdate()-7), 112) ,6) 

DECLARE @GTI_SQL_REPORT VARCHAR(max) 
SET @GTI_SQL_REPORT = 
    'Select 
     [CountryID], 
     COUNT([Document name]) as [inputcount], 
     MONTH([Creation Date]) AS [Creation Month], 
     Year([Creation Date]) as [Creation Year] 
    from ' + @TABLE_NAME + ' 
    WHERE 
     [doc_type_product_type] not in (''CUST'') 
     and [Document_Source] in (''FAX'',''Original'') 
    group by 
     [CountryID], 
     MONTH([Creation Date]) , 
     Year([Creation Date]) 
    order by 
    [CountryID]; ' 

print(@GTI_SQL_REPORT) 
--exec(@GTI_SQL_REPORT)