用于从日期中提取年份的 SQL 查询
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SQL query for extracting year from a date
提问by John Doe
I am trying to create a query that gets only the year from selected dates. I.e. select ASOFDATE from PSASOFDATE;returns 11/15/2012, but I want only 2012. How can I get only the year? I know the YEARfunction can be used, but I'm not sure how.
我正在尝试创建一个仅从选定日期获取年份的查询。即select ASOFDATE from PSASOFDATE;返回11/15/2012，但我只想要2012。我怎么能只得到年份？我知道YEAR可以使用该功能，但我不确定如何使用。
采纳答案by bonCodigo
SELECT YEAR(ASOFDATE) FROM PASOFDATE
Editted: In anycase if your date is a String, let's convert it into a proper date format. And select the year out of it.
编辑：无论如何，如果您的日期是字符串，让我们将其转换为正确的日期格式。并从中选择年份。
SELECT YEAR(STR_TO_DATE(ASOFDATE, '%d-%b-%Y')) FROM PSASOFDATE
Since you are trying Toad, can you check the following code:
既然您正在尝试 Toad，您能否检查以下代码：
SELECT EXTRACT (TO_DATE(YEAR, 'MM/DD/YY') FROM ASOFDATE) FROM PSASOFDATE;
回答by Gee
This worked for me:
这对我有用：
SELECT EXTRACT(YEAR FROM ASOFDATE) FROM PSASOFDATE;
回答by Juan
How about this one?
这个怎么样？
SELECT TO_CHAR(ASOFDATE, 'YYYY') FROM PSASOFDATE
回答by John Woo
just pass the columnName as parameter of YEAR
只需将 columnName 作为参数传递 YEAR
SELECT YEAR(ASOFDATE) from PSASOFDATE;
another is to use DATE_FORMAT
另一种是使用 DATE_FORMAT
SELECT DATE_FORMAT(ASOFDATE, '%Y') from PSASOFDATE;
UPDATE 1
更新 1
I bet the value is varchar with the format MM/dd/YYYY, it that's the case,
我敢打赌该值是格式为 MM/dd/YYYY 的 varchar，就是这种情况，
SELECT YEAR(STR_TO_DATE('11/15/2012', '%m/%d/%Y'));
LAST RESORT if all the queries fail
LAST RESORT 如果所有查询都失败
use SUBSTRING
用 SUBSTRING
SELECT SUBSTRING('11/15/2012', 7, 4)
