如何算数据库的纪录总数

sql="select * from mend_biaoge"
set rs = server.CreateObject("ADODB.Recordset")
rs.Open sql,cn,1,3

j=rs.recordcount
j总是返回值为-1
为什么，书上也是这么些的阿？

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这recordCount就是这样，即使是空集，也返回－1，用
select count(*) as aa from table倒是可以，不过要一个数据集，

asp中怎么用into的办法到一个变量上？？像：
select count(*) into aa from table
？？
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rs.Open sql,cn,1,3

这句改成rs.Open sql,cn,1,1

就可以用rs.Recordcount了
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sql="select * from mend_biaoge"
set rs = server.CreateObject("ADODB.Recordset")
rs.Open sql,cn,1,3
j=rs.count()
select count()
into aa
from table

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1.
sql="select * from mend_biaoge"
set rs = server.CreateObject("ADODB.Recordset")
rs.Open sql,cn,3,3

j=rs.recordcount

2.
sql="select count(*) as num from mend_biaoge"
set rs = server.CreateObject("ADODB.Recordset")
rs.Open sql,cn,1,3
j=rs("num")