SQL获取整数的最后两位数

Question

我需要获取整数的最后两位数.放在表格中的每个元素都是全年,即.YYYY我只想要最后两位数字,以便显示所有字段

YEAR
----
09
00
89

最初的领域是什么

YEAR
----
2009
2000
1989

编辑:我得到投诉说,

HINT: No function matches the given name and argument types. You might need to add explicit type casts.

当我尝试

select right(cast(year as char),2) from subjects;

Answer 1

Postgres从C借用(或继承)了模数运算符:

SET search_path='tmp';

CREATE TABLE lutser ( year integer);

INSERT INTO lutser (year)
        SELECT generate_series(1991,2012)
    ;

SELECT year
    , year / 100 as c2
    , year % 100 AS y2
    FROM lutser
    ;

结果:

CREATE TABLE
INSERT 0 22
 year | c2 | y2 
------+----+----
 1991 | 19 | 91
 1992 | 19 | 92
 1993 | 19 | 93
 1994 | 19 | 94
 1995 | 19 | 95
 1996 | 19 | 96
 1997 | 19 | 97
 1998 | 19 | 98
 1999 | 19 | 99
 2000 | 20 |  0
 2001 | 20 |  1
 2002 | 20 |  2
 2003 | 20 |  3
 2004 | 20 |  4
 2005 | 20 |  5
 2006 | 20 |  6
 2007 | 20 |  7
 2008 | 20 |  8
 2009 | 20 |  9
 2010 | 20 | 10
 2011 | 20 | 11
 2012 | 20 | 12
(22 rows)

Answer 2

select substring(CAST(2012 as CHAR(4)), 3, 2)