sql - 当浮点值存储在 nvarchar 列中时，如何按数字顺序对它们进行排序？

Question

这些是我运行的查询的结果：

10
10.5
11
11.5
12
12.5
13
5
5.5
6
6.5
7
7.5
8
9.5
8.5
9

列的数据类型是nvarchar.

如何按结果排序？

我试过了Order by asc，desc但什么也没做。

Answer 1

用于CAST将值视为数字：

ORDER BY CAST(columnName AS FLOAT)

Answer 2

Alphabetical sorting is different than numeric sorting. Cast your column to a float or real.

select cast(your_column as float) float_col
from your_table
order by float_col;

Ideally, though, you should either

• store floating-point values in a column of type float or real, or
• use an exact numeric type that supports decimals (type numeric or type decimal).

It's not clear from your question whether your application is better off with a float or with an exact numeric.

Answer 3

使用 varchar 你不能......因为它会按字母顺序排列......

那是11会来的7。甚至101会来之前77。

最好float作为数据类型。