MYSQL记录获取2个日期

Question

Currently i require that if time is before noon for current day, then it should take the item_2 value of prev day for current day only. for others it will take, their proper values.

    id  |   item_1 | item_2 | date
    1       205         3       2015-04-07
    2       215         35      2015-04-06
    3       225         15      2015-04-05
    4       235         315     2015-04-04

Expected result wen time is before noon

    id  |   item_1 | item_2 |   sum |    date
    1       205         35      240     2015-04-07
    2       215         35      250     2015-04-06
    3       225         15      240     2015-04-05
    4       235         31      266     2015-04-04

Expected result wen time is after noon

    id  |   item_1 | item_2 |   sum |    date
    1       205         3       208     2015-04-07
    2       215         35      250     2015-04-06
    3       225         15      240     2015-04-05
    4       235         31      266     2015-04-04

Date and time can be used from php and how to manage for prev and current day record in same query. i tried with sub query, but i think it can be done in other way also.

Thanks in advance.

Answer 1

In this case you have to use CASE in your query:

try this:

SET @time := 'BFNOON';
SET @date := '2015-04-07 00:00:00';

SELECT id, item_1, item_2, (item_1 + item_2) AS sum_item, dates FROM (
SELECT id, item_1,
(CASE
WHEN (@time = 'BFNOON' AND dates = @date) THEN 
(
SELECT item_2 FROM records WHERE dates < @date ORDER BY dates DESC  LIMIT 1
) ELSE 
item_2
END ) item_2
, dates 

FROM records ) records

Note: remove declaration and replace @time = 'BFNOON' to check before or after noon and @date with your date value of today

here sqlfiddle as example : http://sqlfiddle.com/#!9/f5dbe/10