MySQL按小时查询数据,没有的补0

吾爱主题阅读：170 2024-04-02 07:58:24 评论：0

需求背景

一个统计接口，前端需要返回两个数组，一个是0-23的小时计数，一个是各小时对应的统计数。

思路直接使用group by查询要统计的表，当某个小时统计数为0时，会没有该小时分组。思考了一下，需要建立辅助表，只有一列小时，再插入0-23共24个小时

1 2 3 CREATE TABLE hours_list ( hour int NOT NULL PRIMARY KEY )

先查小时表，再做连接需要查的表，即可将没有统计数的小时填充上0。这里由于需要查多个表中，create_time在每个小时区间内、且SOURCE_ID等于查询条件的统计之和，所以UNION ALL了多张表

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 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