1

早上好。我有这张桌子：

mysql> select * from Data;
+---------------------------+--------+-------+
| affyId                    | exptId | level |
+---------------------------+--------+-------+
| 31315_at                  | 3      |   250 |
| 31324_at                  | 3      |    91 |
| 31325_at                  | 1      |   191 |
| 31325_at                  | 2      |   101 |
| 31325_at                  | 4      |    51 |
| 31325_at                  | 5      |    71 |
| 31325_at                  | 6      |    31 |
| 31356_at                  | 3      |    91 |
| 31362_at                  | 3      |   260 |
| 31510_s_at                | 3      |   257 |
| 5321_at                   | 4      |    90 |
| 5322_at                   | 4      |    90 |
| 5323_at                   | 4      |    90 |
| 5324_at                   | 3      |    57 |
| 5324_at                   | 4      |    90 |
| 5325_at                   | 4      |    90 |
| AFFX-BioB-3_at            | 3      |    97 |
| AFFX-BioB-5_at            | 3      |    20 |
| AFFX-BioB-M_at            | 3      |    20 |
| AFFX-BioB-M_at            | 5      |   214 |
| AFFX-BioB-M_at            | 7      |    20 |
| AFFX-BioB-M_at            | 8      |    40 |
| AFFX-BioB-M_at            | 9      |    20 |
| AFFX-HSAC07/X00351_M_at   | 3      |    86 |
| AFFX-HUMBAPDH/M33197_3_st | 3      |   277 |
| AFFX-HUMTFFR/M11507_at    | 3      |    90 |
| AFFX-M27830_3_at          | 3      |   271 |
| AFFX-MurIL10_at           | 3      |     8 |
| AFFX-MurIL10_at           | 5      |     8 |
| AFFX-MurIL10_at           | 6      |     4 |
| AFFX-MurIL2_at            | 3      |    20 |
| AFFX-MurIL4_at            | 5      |    78 |
| AFFX-MurIL4_at            | 6      |    20 |
| U95-32123_at              | 1      |   128 |
| U95-32123_at              | 2      |   128 |
| U98-40474_at              | 1      |    57 |
| U98-40474_at              | 2      |    57 |
+---------------------------+--------+-------+
37 rows in set (0.00 sec)

如果我想在所有实验中寻找每个阵列探针 (affyId) 的平均表达水平 (level)，我会SELECT affyId, AVG(level) AS average FROM Data GROUP BY affyId;

但是，我无法弄清楚如何查找每个实验的每个数组探针（affyId）的平均表达水平......它必须与上次查询类似，但我没有获得好的结果......有什么帮助吗？

PD：有人告诉我，如果有人解决了我的问题，我应该给予一些声誉或点击一些绿色按钮......对吗？我该怎么做？我是这个网站的新手...

4

2 回答 2

0

只需将其添加到group by子句中

SELECT affyId, exptId, AVG(level) AS average 
FROM Data
GROUP BY affyId, exptId;
于 2013-10-19T12:10:57.797 回答
0

这显示了每个 affyId 的平均值：

SELECT affyId, AVG(level) AS average FROM Data GROUP BY affyId

这是每个 exptId 的平均值：

SELECT exptId, AVG(level) AS average FROM Data GROUP BY exptId

这是每个 affyId 中每个 exptId 的平均值：

SELECT affyId, exptId, AVG(level) AS average FROM Data GROUP BY exptId, affyId
于 2013-10-19T12:11:41.103 回答