需求背景
一個統(tǒng)計接口，前端需要返回兩個數(shù)組，一個是0-23的小時計數(shù)，一個是各小時對應(yīng)的統(tǒng)計數(shù)。
思路 直接使用group by查詢要統(tǒng)計的表，當(dāng)某個小時統(tǒng)計數(shù)為0時，會沒有該小時分組。思考了一下，需要建立輔助表，只有一列小時，再插入0-23共24個小時
CREATE TABLE hours_list (
hour int NOT NULL PRIMARY KEY
)
先查小時表，再做連接需要查的表，即可將沒有統(tǒng)計數(shù)的小時填充上0。這里由于需要查多個表中，create_time在每個小時區(qū)間內(nèi)、且SOURCE_ID等于查詢條件的統(tǒng)計之和，所以UNION ALL了多張表
SELECT
t.HOUR,
sum(t.HOUR_COUNT) hourCount
FROM
(SELECT
hs. HOUR AS HOUR,
COUNT(cs.RECORD_ID) AS HOUR_COUNT
FROM
cbc_hours_list hs
LEFT JOIN cbc_source_0002 cs ON HOUR (cs.create_time) = hs. HOUR
AND cs.create_time > #{startTime}
AND cs.create_time = #{endTime}
#if sourceId?exists sourceId !=''>
AND SOURCE_ID = #{sourceId}
/#if>
GROUP BY
hs. HOUR
UNION ALL
SELECT
hs.HOUR AS HOUR,
COUNT(cs.RECORD_ID) AS HOUR_COUNT
FROM
cbc_hours_list hs
LEFT JOIN cbc_source_hs cs ON HOUR (cs.create_time) = hs. HOUR
AND cs.create_time > #{startTime}
AND cs.create_time = #{endTime}
#if sourceId?exists sourceId !=''>
AND SOURCE_ID = #{sourceId}
/#if>
GROUP BY
hs. HOUR
UNION ALL
SELECT
hs.HOUR AS HOUR,
COUNT(cs.RECORD_ID) AS HOUR_COUNT
FROM
cbc_hours_list hs
LEFT JOIN cbc_source_kfyj cs ON HOUR (cs.create_time) = hs. HOUR
AND cs.create_time > #{startTime}
AND cs.create_time = #{endTime}
#if sourceId?exists sourceId !=''>
AND SOURCE_ID = #{sourceId}
/#if>
GROUP BY
hs. HOUR
UNION ALL
SELECT
hs.HOUR AS HOUR,
COUNT(cs.RECORD_ID) AS HOUR_COUNT
FROM
cbc_hours_list hs
LEFT JOIN cbc_source_his_0002 cs ON HOUR (cs.create_time) = hs. HOUR
AND cs.create_time > #{startTime}
AND cs.create_time = #{endTime}
#if sourceId?exists sourceId !=''>
AND SOURCE_ID = #{sourceId}
/#if>
GROUP BY
hs. HOUR
UNION ALL
SELECT
hs.HOUR AS HOUR,
COUNT(cs.RECORD_ID) AS HOUR_COUNT
FROM
cbc_hours_list hs
LEFT JOIN cbc_source_his_hs cs ON HOUR (cs.create_time) = hs. HOUR
AND cs.create_time > #{startTime}
AND cs.create_time = #{endTime}
#if sourceId?exists sourceId !=''>
AND SOURCE_ID = #{sourceId}
/#if>
GROUP BY
hs. HOUR
UNION ALL
SELECT
hs.HOUR AS HOUR,
COUNT(cs.RECORD_ID) AS HOUR_COUNT
FROM
cbc_hours_list hs
LEFT JOIN cbc_source_his_kfyj cs ON HOUR (cs.create_time) = hs. HOUR
AND cs.create_time > #{startTime}
AND cs.create_time = #{endTime}
#if sourceId?exists sourceId !=''>
AND SOURCE_ID = #{sourceId}
/#if>
GROUP BY
hs. HOUR) t
GROUP BY
t.hour
效果
統(tǒng)計數(shù)為0的小時也可以查出來了。
到此這篇關(guān)于MySQL按小時查詢數(shù)據(jù),沒有的補0的文章就介紹到這了,更多相關(guān)MySQL按小時查詢數(shù)據(jù)內(nèi)容請搜索腳本之家以前的文章或繼續(xù)瀏覽下面的相關(guān)文章希望大家以后多多支持腳本之家！
您可能感興趣的文章:- 詳解MySQL子查詢（嵌套查詢）、聯(lián)結(jié)表、組合查詢
- 詳解MySQL的sql_mode查詢與設(shè)置
- MySQL 子查詢和分組查詢
- MySQL 分組查詢和聚合函數(shù)
- Mysql 查詢JSON結(jié)果的相關(guān)函數(shù)匯總
- MySQL 查詢的排序、分頁相關(guān)
- MySql查詢時間段的方法
- MySQL中基本的多表連接查詢教程
- MySQL里面的子查詢實例
- 詳解mysql 組合查詢
