Question

• 如何比较信通厅中的日期部分:

I wrote the following query but I get a syntax error:

select id,name from h_history 
 where ( h_date::DATETIME YEAR TO MONTH >= 2/2012 )
   and ( h_date::DATETIME YEAR TO MONTH <= 1/2013 )

1. 与年份和月份比较的大麻

如何做到这一点?

Answer 1

如果你重新使用DATETIME线路,你需要正确制定这些数值。原文照发:

select id,name from h_history 
 where ( h_date::DATETIME YEAR TO MONTH >= 2/2012 )
   and ( h_date::DATETIME YEAR TO MONTH <= 1/2013 )

<代码>2/2012是一种等于0的立体分类,迄今为止,没有从ger化物中提取任何含蓄的成分,反之亦然。

你可以写:

-- Query 1
SELECT id, name
  FROM h_history 
 WHERE (h_date::DATETIME YEAR TO MONTH >= DATETIME(2012-02) YEAR TO MONTH)
   AND (h_date::DATETIME YEAR TO MONTH <= DATETIME(2013-01) YEAR TO MONTH)

这ver而准确。你们可以使用一个捷径:

-- Query 2
SELECT id, name
  FROM h_history 
 WHERE (h_date::DATETIME YEAR TO MONTH >=  2012-02 )
   AND (h_date::DATETIME YEAR TO MONTH <=  2013-01 )

然而,由于<代码>h_date<>/code> 是日报,而不是“日报”,因此还有其他选择。 YEAR, MONTH, 录音通知, 排日职能从国名中提取明显部分(如果你通过国名监督署履行这一职能,则国名监督署将受到胁迫,然后处理)。唯一完全由当地独立的DATE建筑商是MDY功能,需要3个论点,即月、日和年。所有扼杀性代表都须由当地人解释,因此,在一切时间都赢得工作。

也可以做:

-- Query 3
SELECT id, name
  FROM h_history 
 WHERE (h_date >= MDY(2,  1, 2012))
   AND (h_date <= MDY(1, 31, 2013))

或:

-- Query 4
SELECT id, name
  FROM h_history 
 WHERE ((YEAR(h_date) = 2012 AND MONTH(h_date) >= 2) OR YEAR(h_date) >= 2013)
   AND ((YEAR(h_date) = 2013 AND MONTH(h_date) <= 1) OR YEAR(h_date) <  2013)

或:

-- Query 5
SELECT id, name
  FROM h_history 
 WHERE (YEAR(h_date) * 100 + MONTH(h_date)) >= 201202
   AND (YEAR(h_date) * 100 + MONTH(h_date)) <= 201301

鉴于这一选择,我或许会把表2作为简明扼要但准确的,或或许是表5,但所有问询都可用。

如果h_date 是某种DATETIME类型的一个栏目,而且你需要比较部分的DATETIME,你可以使用(如Query 1所示)的投放或文稿功能。这往往ver。

Answer 2

Assuming that h_date is a proper date field, why wouldn t

SELECT 
      id
    , name
FROM h_history 
WHERE h_date >=  02/01/2012  and h_date <=  01/31/2013

你们的工作?

Answer 3

询问如下:

SELECT
  id,name 
FROM h_history 
WHERE
  h_date >= MDY(2, 1, 2012)
  AND h_date < MDY(2, 1, 2013)

Answer 4

select * from table t where MONTH(t.date) = 12

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