我有这个表/数据结构:
ID Area Postcode
------------------------
1 "Area 1" "EN1 1NE"
2 "Area 2" "AB2 3BA"
3 "Area 1" "EN1 1NE"
4 "Area 3" "XY4 5ZA"
5 "Area 4" "MN6 5OP"
第1行和第3行有重复的邮政编码和区域。我需要一个输出如下计数的查询:
Area Postcode Count
----------------------------
"Area 1" "EN1 1NE" 2
"Area 2" "AB2 3BA" 1
"Area 3" "XY4 5ZA" 1
"Area 4" "MN6 5OP" 1
我用DISTINCT和/或COUNT和/或子查询进行了搜索和播放,但在这里真的输了! #弱-SQL福
谢谢! 本
答案 0 :(得分:3)
您可以将count(*)与group by一起使用:
select Area, Postcode, count(*) from TABLE group by Area, Postcode;
答案 1 :(得分:2)
必须在ALIAS
COUNT
内使用反引号来转义保留字。
SELECT Area,
Postcode,
COUNT(ID) as `Count`
FROM tableName
Group BY Area, Postcode
ORDER BY Area;