Mysql 如何";“合并”;按日期列出的两个结果集
我正在尝试合并以下两个SQL查询的结果: 上传表格Mysql 如何";“合并”;按日期列出的两个结果集,mysql,sql,join,Mysql,Sql,Join,我正在尝试合并以下两个SQL查询的结果: 上传表格 SELECT DATE(`timestamp`), SUM(uploaded) AS total_upload FROM uploads; date total_download 2014-09-11 1000 2014-09-12 1000 2014-09-13 1000 SELECT DATE(`timestamp`), SUM(downloaded) AS total_download FROM
SELECT DATE(`timestamp`), SUM(uploaded) AS total_upload FROM uploads;
date total_download
2014-09-11 1000
2014-09-12 1000
2014-09-13 1000
SELECT DATE(`timestamp`), SUM(downloaded) AS total_download FROM downloads;
date total_upload
2014-09-09 1000
2014-09-10 1000
2014-09-11 1000
下载表
SELECT DATE(`timestamp`), SUM(uploaded) AS total_upload FROM uploads;
date total_download
2014-09-11 1000
2014-09-12 1000
2014-09-13 1000
SELECT DATE(`timestamp`), SUM(downloaded) AS total_download FROM downloads;
date total_upload
2014-09-09 1000
2014-09-10 1000
2014-09-11 1000
我希望得到以下结果,如果没有下载,则结果为空白,如果没有上传,则结果为空白:
date total_download total_upload
2014-09-09 1000
2014-09-10 1000
2014-09-11 1000 1000
2014-09-12 1000
2014-09-13 1000
我想我可以在下载日期=上传日期离开加入表格,但显然没有上传的日子将不复存在。如何正确地合并这些结果?使用
完全连接和合并()
语法可能不正确;我对MySQL已经生疏了
编辑:如果您想要完全空白,则需要将:COALESCE(CAST(u.total\u upload AS varchar),“”)替换为total\u upload
或类似内容。但请注意,这实际上会将输出数据类型更改为字符