Question

此查询有效：

select ist_id,  ist_opis , CAST(ist_sifra as float ) as sifra 
from IZOBRAZBENA_STOPNJA 
where ist_aktivno<>0 
order by sifra

但如果我只想看到sifra = 5时我得到“无效的列名'sifra'。”

select ist_id,  ist_opis , CAST(ist_sifra as float ) as sifra 
from IZOBRAZBENA_STOPNJA 
where ist_aktivno<>0 and sifra = 5
order by sifra

我尝试在另一个select中使用sql语句进行包装，然后使用“where sifra = 5”它也失败了..

Answer 1

是的，这是事实。你可以做点什么

其中isk aktiv＆lt;＆gt; 0和ist_sifra = 5
或
其中isk aktivno＆lt;＆gt; 0和CAST（ist_sifra as float）= 5

Answer 2

因为没有名为sifra的列。您也可以使用where子句进行转换

select ist_id,  ist_opis , CAST(ist_sifra as float ) as sifra 
from IZOBRAZBENA_STOPNJA 
where ist_aktivno<>0 and CAST(ist_sifra as float ) = 5
order by sifra

或参考未发布的专栏

select ist_id,  ist_opis , CAST(ist_sifra as float ) as sifra 
from IZOBRAZBENA_STOPNJA 
where ist_aktivno<>0 and ist_sifra = 5
order by sifra

SQL Server 2005无法引用已“已转换”的列

2 个答案: