一个简单的SQL问题。(30分)

有一个表：名字叫Phones(PhoneNumber, FileName)
我想统计表中PhoneNumber的重复次数，写得SQL：
SQLStr := 'select PhoneNumber, count(PhoneNumber) as Total, FileName from Phones where FileName = ''' + FileName + ''' group by PhoneNumber having count(PhoneNumber) > 1';
ADOQuery.SQL.Add(SQLStr);
ADOQuery.Open;

执行的时候总是报错：试图执行的查询中不包含作为合计函数一部分的特定表达式'FileName'。请问这是怎么回事？
是我的SQL语句写错了？？

是错了:
'select PhoneNumber, count(PhoneNumber) as Total, FileName from Phones where FileName = ''' + FileName + ''' group by PhoneNumber,FileName having count(PhoneNumber) > 1'
不行去掉FileName选择字段,因为你在条件中不是已经限定FileName的值了

group by 表示分组，
而你所引用的FieldName并没有使用聚合函数。

可以尝试使用类似：Max,First,Last等聚合函数
SQLStr := 'select PhoneNumber, count(PhoneNumber) as Total, Max(FileName) from Phones where FileName = ''' + FileName + ''' group by PhoneNumber having count(PhoneNumber) > 1'

SQL := 'select PhoneNumber,count(PhoneNumber) as PhoneNumber
from Phones
where FileName = ''' + FileName + '''
group by PhoneNumber
having count(PhoneNumber)>1'