關於月 季 周 日的統計完善
之前寫的那個只能獲取固定的某年，某季，某月，某天的統計，這讓我做報表的很難受，於是上網百度加自己理解寫了如下的方法
凡是結果同月的第二個方法便於一個報表統計，方法只需寫一個，謹慎選擇
月：
1.
SELECT
SUM( CASE MONTH ( a.createTime ) WHEN '1' THEN 1 ELSE 0 END ) AS january,
SUM( CASE MONTH ( a.createTime ) WHEN '2' THEN 1 ELSE 0 END ) AS february,
SUM( CASE MONTH ( a.createTime ) WHEN '3' THEN 1 ELSE 0 END ) AS march,
SUM( CASE MONTH ( a.createTime ) WHEN '4' THEN 1 ELSE 0 END ) AS april,
SUM( CASE MONTH ( a.createTime ) WHEN '5' THEN 1 ELSE 0 END ) AS may,
SUM( CASE MONTH ( a.createTime ) WHEN '6' THEN 1 ELSE 0 END ) AS june,
SUM( CASE MONTH ( a.createTime ) WHEN '7' THEN 1 ELSE 0 END ) AS july,
SUM( CASE MONTH ( a.createTime ) WHEN '8' THEN 1 ELSE 0 END ) AS august,
SUM( CASE MONTH ( a.createTime ) WHEN '9' THEN 1 ELSE 0 END ) AS september,
SUM( CASE MONTH ( a.createTime ) WHEN '10' THEN 1 ELSE 0 END ) AS october,
SUM( CASE MONTH ( a.createTime ) WHEN '11' THEN 1 ELSE 0 END ) AS november,
SUM( CASE MONTH ( a.createTime ) WHEN '12' THEN 1 ELSE 0 END ) AS december
FROM
`gm_buyerproduct` a
WHERE
YEAR(createTime) = YEAR("2018-9-6")
如果你就要確定的12個月的統計，用這個很清楚，但報表的橫座標就是固定值了，不好做其他的方法統計
2.
SELECT COUNT(createTime) countStatus,
MONTH(createTime) AS monthflg
FROM
`gm_buyerproduct`
WHERE
YEAR(createTime)=YEAR("2018-12-6")
GROUP BY monthflg
這方法好處是橫座標是變數，但是隻能統計月份有數值，沒數值不會顯示，導致結構可能是：1月，2月，4月有值顯示，3月沒值就不顯示
季：
1.
SELECT
SUM( CASE QUARTER ( a.createTime ) WHEN '1' THEN 1 ELSE 0 END ) AS aa,
SUM( CASE QUARTER ( a.createTime ) WHEN '2' THEN 1 ELSE 0 END ) AS ss,
SUM( CASE QUARTER ( a.createTime ) WHEN '3' THEN 1 ELSE 0 END ) AS dd,
SUM( CASE QUARTER ( a.createTime ) WHEN '4' THEN 1 ELSE 0 END ) AS ff
FROM
`gm_buyerproduct` a
WHERE
YEAR(createTime) = YEAR("2018-9-6")
效果如月1
2.
SELECT COUNT(createTime) createTime,
QUARTER(createTime) modifiedTime
FROM
`gm_buyerproduct`
WHERE
YEAR(createTime) = YEAR("2018-8-8")
GROUP BY modifiedTime
同月2
周：
SELECT COUNT(createTime) countStatus,
WEEK(createTime) weeks
FROM
`gm_buyerproduct`
WHERE
MONTH(createTime)=MONTH("2018-12-19")AND YEAR(createTime)=YEAR("2018-12-16")
GROUP BY weeks
結果同月2，我這是統計一個月的周，統計某年所有周將MONTH(createTime)=MONTH("2018-12-19")AND 去了就行
天：
SELECT DATE_FORMAT (createTime,"%m-%d") createTimes,COUNT(createTime) countStatus ,YEAR(createTime) years
FROM `gm_buyerproduct`
WHERE WEEK(createTime)=WEEK("2018-12-16") AND YEAR(createTime)=YEAR("2018-12-16")
GROUP BY createTimes
結果同月2這是統計某周的7天，根據需求來加減條件