如何计算Oracle数据库中具有相同起始字母的行数

Question

我有一张桌子客户:

????????????????????
? CustomerID ? ... ?
????????????????????
? ACC20011   ? ... ?
? ACC30122   ? ... ?
? ACC12356   ? ... ?
? EVG12345   ? ... ?
? DAA23445   ? ... ?
? DAA23548   ? ... ?
????????????????????

我需要以下输出:

??????????????????????
? CustomerID ? Count ?
??????????????????????
?    Acc     ?  3    ?
?    EVG     ?  1    ?
?    DAA     ?  2    ?
??????????????????????

我写了以下查询.但我知道错了.请纠正我.

select CustomerID , count(*) as Count 
from Customers
where CustomerID is like 'ACC%'

Answer 1

试试这个查询:

SELECT SUBSTR(CustomerID, 1, 3) AS CustomerID, COUNT(*)
FROM Customers
GROUP BY SUBSTR(CustomerID, 1, 3)