Php MySQL-将行合并为一行
我搜索了各种各样的问题,但没有找到答案。 我有一个MySQL表“团队”:Php MySQL-将行合并为一行,php,mysql,sql,database,Php,Mysql,Sql,Database,我搜索了各种各样的问题,但没有找到答案。 我有一个MySQL表“团队”: +--+----+------+ |id|name|active| +--+----+------+ |1 |bla |1 | |2 |blu |0 | |3 |croc|1 | |4 |bold|1 | |5 |foo |1 | |6 |bar |0 | +--+----+------+ 和一个表“数据”: +----+-------+----+ |team|projec
+--+----+------+
|id|name|active|
+--+----+------+
|1 |bla |1 |
|2 |blu |0 |
|3 |croc|1 |
|4 |bold|1 |
|5 |foo |1 |
|6 |bar |0 |
+--+----+------+
和一个表“数据”:
+----+-------+----+
|team|project|time|
+----+-------+----+
|2 |some |1 |
|2 |some2 |5 |
|3 |one |16 |
|3 |one2 |100 |
|5 |more |2 |
|5 |more2 |60 |
+----+-------+----+
在PHP中,我查询的数据如下:
SELECT t.name, t.active, d.time
FROM teams t
RIGHT JOIN data d ON (t.id = d.team)
ORDER BY t.id
一切正常,我的结果如下:
+----+------+----+
|name|active|time|
+----+------+----+
|blu |0 |1 |
|blu |0 |5 |
|croc|1 |16 |
|croc|1 |100 |
|foo |1 |2 |
|foo |1 |60 |
+----+------+----+
+----+------+---+---+
|name|active|t1 |t2 |
+----+------+---+---+
|blu |0 |1 |5 |
|croc|1 |16 |100|
|foo |1 |2 |60 |
+----+------+---+---+
SELECT
teams.name,
teams.active,
min(d1.time) t1,
max(d2.time) t2
FROM
teams INNER JOIN data d1
ON teams.id=d1.team
LEFT JOIN data d2
ON teams.id=d2.team AND d1.time<d2.time
GROUP BY
teams.name,
teams.active
…但我希望我的结果如下所示:
+----+------+----+
|name|active|time|
+----+------+----+
|blu |0 |1 |
|blu |0 |5 |
|croc|1 |16 |
|croc|1 |100 |
|foo |1 |2 |
|foo |1 |60 |
+----+------+----+
+----+------+---+---+
|name|active|t1 |t2 |
+----+------+---+---+
|blu |0 |1 |5 |
|croc|1 |16 |100|
|foo |1 |2 |60 |
+----+------+---+---+
SELECT
teams.name,
teams.active,
min(d1.time) t1,
max(d2.time) t2
FROM
teams INNER JOIN data d1
ON teams.id=d1.team
LEFT JOIN data d2
ON teams.id=d2.team AND d1.time<d2.time
GROUP BY
teams.name,
teams.active
所以。。。我怎样才能到达这里?我希望我没有忽略一个已经提出的问题…:(
多谢各位
编辑:首先,谢谢大家,但我忘了一些东西…也可能是one2不存在…试试这个
SELECT t.name, t.active,
min(time) t1, max(time)t2
FROM teams t
RIGHT JOIN data d ON (t.id = d.team)
group by name
ORDER BY t.id
SELECT t.name, t.active,
min(time) t1, if ( max(time) is not null and max(time) <> min(time) , max(time), null )t2
FROM teams t
RIGHT JOIN data d ON (t.id = d.team)
group by name
ORDER BY t.id
编辑:
试试这个
SELECT t.name, t.active,
min(time) t1, max(time)t2
FROM teams t
RIGHT JOIN data d ON (t.id = d.team)
group by name
ORDER BY t.id
SELECT t.name, t.active,
min(time) t1, if ( max(time) is not null and max(time) <> min(time) , max(time), null )t2
FROM teams t
RIGHT JOIN data d ON (t.id = d.team)
group by name
ORDER BY t.id
选择t.name,t.active,
最小值(时间)t1,如果最大值(时间)不为空,最大值(时间)最小值(时间),最大值(时间),空)t2
来自t队
右连接数据d ON(t.id=d.team)
按名称分组
按t.id订购
如果每个团队最多有两排,我会使用以下方法:
+----+------+----+
|name|active|time|
+----+------+----+
|blu |0 |1 |
|blu |0 |5 |
|croc|1 |16 |
|croc|1 |100 |
|foo |1 |2 |
|foo |1 |60 |
+----+------+----+
+----+------+---+---+
|name|active|t1 |t2 |
+----+------+---+---+
|blu |0 |1 |5 |
|croc|1 |16 |100|
|foo |1 |2 |60 |
+----+------+---+---+
SELECT
teams.name,
teams.active,
min(d1.time) t1,
max(d2.time) t2
FROM
teams INNER JOIN data d1
ON teams.id=d1.team
LEFT JOIN data d2
ON teams.id=d2.team AND d1.time<d2.time
GROUP BY
teams.name,
teams.active
选择
团队名称,
团队,积极,
最小值(d1时间)t1,
最大(d2时间)t2
从…起
团队内部连接数据d1
在团队中。id=d1.team
左连接数据d2
在teams.id=d2.team和d1.timeyou不需要。你想要的基本上是一个pivot表,mysql不支持。在你的客户机代码中进行转换。它可以用sql编写,但它变得非常难看,非常快。尽管我不得不同意@MarcB:它可能会变得混乱!他已经在他想要的结果t1和t2
,如果他有三个,他还应该提到t3
@user2329363,如果一个2不存在,你想要什么结果?有可能,项目“一”存在,但项目“一”不存在。在这种情况下,“t2”应该为空。但在你的情况下,“t2”的值为“t1”。现在我有另一个问题……它也可能存在假设“one”不存在,但“one2”存在。那么“t1”应该为null。我如何管理它?我的查询也适用于第二个建议,否则您如何知道它的t1或t2时间值?