SQL - 从日期时间字段中仅选择“年份”
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SQL - Select only 'Year' from DateTime field
提问by kekimian
My DB is an SQL Server 2012. I try to select only the year from my datetime filed. The date format is dd/mm/yyyy 00:00:00. Here is my queries:
我的数据库是 SQL Server 2012。我尝试仅从我提交的日期时间中选择年份。日期格式为 dd/mm/yyyy 00:00:00。这是我的查询：
SELECT
,YEAR(DateTime)
FROM MayTable
But when I run my queries I get this error:
但是，当我运行查询时，出现此错误：
Conversion failed when converting date and/or time from character string.
从字符串转换日期和/或时间时转换失败。
回答by Martin Smith
You should store this information in a column of appropriate datatype in the first place.
您应该首先将此信息存储在适当数据类型的列中。
But if I understand your comment correctly this is not a table of your own design. You can use
但是，如果我正确理解您的评论，这不是您自己设计的表格。您可以使用
SELECT CAST(SUBSTRING(DateTime, 7, 4) AS INT)
FROM MyTable;
Or
或者
SET DATEFORMAT DMY;
SELECT YEAR(DateTime)
FROM MyTable;
