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程序运行速度试验结果：
1。作相同的分支条件判断：if 比 select慢。
用以下程序测试：
<%
dim tttt1,ttt2
session(“ii”)=0
for sn=0 to 5
ttt1=now()
for i=0 to 300000
if session(“ii”)=0 then
session(“ii”)=1
else
if session(“ii”)=1 then
session(“ii”)=2
else
if session(“ii”)=2 then
session(“ii”)=3
else
session(“ii”)=0
end if
end if
end if
next
ttt2=now()
tou=ttt2-ttt1
response.write sn&”、”&tou*24*60*60&”<br>”
next
for sn=0 to 5
ttt1=now()
for i=0 to 300000
select case session(“ii”)
case 0
session(“ii”)=1
case 1
session(“ii”)=2
case 2
session(“ii”)=3
case 3
session(“ii”)=0
end select
next
ttt2=now()
tou=ttt2-ttt1
response.write sn&”、”&tou*24*60*60&”<br>”
next
%>
2, 如果把上例中的session对象改为用普通的变量存。速度会快差不多8倍
3,进行字符串连接时往中间加入相同多的字符串，基数越大，越慢。
通过下面的程序测试：
<%
dim tttt1,ttt2
session(“ii”)=0
for sn=0 to 5
ttt1=now()
txt=””
for i=0 to 10000
txt=”a”&txt
next
ttt2=now()
tou=ttt2-ttt1
response.write sn&”、”&tou*24*60*60&”<br>”
next
%>
进行同样长字节的字符连接时，汉字比英文快4倍，通过下面的程序测试
<%
dim tttt1,ttt2
for sn=0 to 5
ttt1=now()
txt=””
for i=0 to 20000
txt=”人”&txt
next
ttt2=now()
tou=ttt2-ttt1
response.write sn&”、”&tou*24*60*60&”<br>”
next
txt=””
for sn=0 to 5
ttt1=now()
txt=””
for i=0 to 20000
txt=”aa”&txt
next
ttt2=now()
tou=ttt2-ttt1
response.write sn&”、”&tou*24*60*60&”<br>”
next
%>
用for 循环比do while循环要快得多，用下面的程序测试，虽然for循环中要多一个变量，
<%
dim tttt1,ttt2
for sn=0 to 5
ttt1=now()
i=0
do while i<=100000
i=i+1
loop
ttt2=now()
tou=ttt2-ttt1
response.write sn&”、”&tou*24*60*60&”<br>”
next
for sn=0 to 5
ttt1=now()
ii=0
for i=0 to 100000
ii=ii+1
next
ttt2=now()
tou=ttt2-ttt1
response.write sn&”、”&tou*24*60*60&”<br>”
next
%>
定义5000个一个字符的session并不比定义5000个有5000个字符串长的session少花很多时间，两者时间差仅为近一倍，用一秒多钟。倒是生成这个5000个字符长的变量花了不少的时间，<%
dim tttt1,ttt2
c=”a”
for sn=0 to 5
session.abandon
ttt1=now()
for i=0 to 5000
session(“s”&i)=c
next
ttt2=now()
tou=ttt2-ttt1
response.write sn&”、”&tou*24*60*60&”:”&session(“s”&i-1)&”<br>”
next
for i=0 to 5000
c=”a”&c
next
for sn=0 to 5
session.abandon
ttt1=now()
for i=0 to 5000
session(“s”&i)=c
next
ttt2=now()
tou=ttt2-ttt1
response.write sn&”、”&tou*24*60*60&”:” &session(“s”&i-1)&”<br>”
next
%>
这段程序从sn＝3起就很慢,而前面非常快
<!–#include file=”filetou.asp”–>
<%
dim tttt1,ttt2
for sn=0 to 5
ttt1=now()
for i=1 to 20
sql =”select 名称 from user where 名称=阿余”
set rs=server.createobject(“adodb.recordset”)
rs.open sql,conn,1,3
rs(“名称”)=”阿余”
rs.update
rs.close
next
ttt2=now()
tou=ttt2-ttt1
response.write sn&”、”&tou*24*60*60&”:”&session(“s”&i-1)&”<br>”
next
%>
而这样就快多了。看来建对象很要花些时间，还有，用move 0,1 和 movefirst 相比速度没有什么差别。
<!–#include file=”filetou.asp”–>
<%
sql =”select 名称 from user where 名称=阿余”
set rs=server.createobject(“adodb.recordset”)
rs.open sql,conn,1,3
dim tttt1,ttt2
for sn=0 to 5
ttt1=now()
for i=1 to 700
rs(“名称”)=”阿余”
rs.update
rs.movefirst
next
ttt2=now()
tou=ttt2-ttt1
response.write sn&”、”&tou*24*60*60&”:”&session(“s”&i-1)&”<br>”
next
%>
而这两种方式相比，后者要慢3倍，可能是后者要重新查询，但比前面的用rs建查询后又去改，改了又关，相比，要快了不知多少。
<!–#include file=”filetou.asp”–>
<%
sql =”select 名称 from user where 名称=阿余”
set rs=server.createobject(“adodb.recordset”)
rs.open sql,conn,1,3
dim tttt1,ttt2
for sn=0 to 5
ttt1=now()
for i=1 to 700
rs(“名称”)=”阿余”
rs.update
rs.movefirst
next
ttt2=now()
tou=ttt2-ttt1
response.write sn&”、”&tou*24*60*60&”:”&session(“s”&i-1)&”<br>”
next
for sn=0 to 5
ttt1=now()
for i=1 to 700
sql=”update user set 名称=阿余 where 名称=阿余”
conn.execute sql,0,-1
next
ttt2=now()
tou=ttt2-ttt1
response.write sn&”、”&tou*24*60*60&”:”&session(“s”&i-1)&”<br>”
next
%>
新加一万条记录谁快？第一种方法用31秒，后者直到超时仍未完成。不得已，少掉一个0，1000条是，后者慢一半。
<!–#include file=”filetou.asp”–>
<%
sql =”select 名称 from user where id=0″
set rs=server.createobject(“adodb.recordset”)
rs.open sql,conn,1,3
dim tttt1,ttt2
ttt1=now()
for i=1 to 10000
rs.addnew
rs(“名称”)=”阿余a”
rs.update
next
ttt2=now()
tou=ttt2-ttt1
response.write sn&”、”&tou*24*60*60&”:”&session(“s”&i-1)&”<br>”
ttt1=now()
for i=1 to 10000
sql=” insert into user (名称) values(阿余b)”
conn.execute sql,0,-1
next
ttt2=now()
tou=ttt2-ttt1
response.write sn&”、”&tou*24*60*60&”:”&session(“s”&i-1)&”<br>”
%>
下面的程序结果说明rs新增记录较快，而删除较慢，用conn新增慢，但删除很快。
运行的结果为：
、3.00000007264316:
、7.99999998416752:
、1.99999983888119:
、0:
后来用rs新增记录5000条，并用conn删除这5000条， 结果为：
、17.000000202097:
、1.00000023376197:
程序为：
<!–#include file=”filetou.asp”–>
<%
dim tttt1,ttt2
ttt1=now()
sql =”select 名称 from user where id=0″
set rs=server.createobject(“adodb.recordset”)
rs.open sql,conn,1,3
for i=1 to 1000
rs.addnew
rs(“名称”)=”阿余a”
rs.update
next
ttt2=now()
tou=ttt2-ttt1
response.write sn&”、”&tou*24*60*60&”:”&session(“s”&i-1)&”<br>”
ttt1=now()
for i=1 to 1000
sql=” insert into user (名称) values(阿余b)”
conn.execute sql,0,-1
next
ttt2=now()
tou=ttt2-ttt1
response.write sn&”、”&tou*24*60*60&”:”&session(“s”&i-1)&”<br>”
ttt1=now()
sql =”select 名称 from user where 名称=阿余a”
set rs=server.createobject(“adodb.recordset”)
rs.open sql,conn,1,3
do while not rs.eof
rs.delete
rs.update
rs.move 0,1
loop
ttt2=now()
tou=ttt2-ttt1
response.write sn&”、”&tou*24*60*60&”:”&session(“s”&i-1)&”<br>”
ttt1=now()
sql =”delete from user where 名称=阿余b”
conn.execute sql,0,-1
ttt2=now()
tou=ttt2-ttt1
response.write sn&”、”&tou*24*60*60&”:”&session(“s”&i-1)&”<br>”
%>
