MySQL如何獲取按語句分組的行數

Question

我試圖獲取在每個結果行中分組在一起的行數的計數。 例如：

SELECT * FROM表GROUP BY Transid，下表中的其他ID

id      transid  other id
------------------------------
|1      |1        |1        |
|2      |1        |1        |
|3      |1        |1        |
|4      |1        |2        |
|5      |1        |2        |
|6      |1        |2        |
|7      |2        |1        |
|8      |2        |1        |
|9      |2        |2        |
|10     |3        |1        |
|11     |3        |1        |

結果：

 id      transid  other id
------------------------------
|1      |1        |1        |
|4      |1        |2        |
|7      |2        |1        |
|10     |2        |2        |
|11     |3        |1        |

我怎樣才能得到：

 id      transid  other id   count
-------------------------------------
|1      |1        |1     |  3
|4      |1        |2     |  3
|7      |2        |1     |  2
|9      |2        |2     |  1
|10     |3        |1     |  2

謝謝。

Answer 1

選擇分組集合的min(id) ，然后使用count （）獲得集合計數

Select min(id), transid, [other id], count(*) count
from table
Group by transid, [other id]

Answer 2

如果您要做的只是計算重復的次數，則只需

Select Count(*), col1, col2 from tbl
group by col1, col2