数据库的SQL

Question

Public SqlConn As ADODB.Connection
On Error GoTo Handler
Set SqlConn = New ADODB.Connection
SqlConn.CursorLocation = adUseClient
ConnStr = "Provider=SQLOLEDB.1;Password=sa;Persist Security Info=True;User ID=sa;Data Source=myserver"
SqlConn.ConnectionString = ConnStr
SqlConn.Open

dim rs as adodb.recordset, sqlstr as string

sqlstr= "select * from table"
set rs = Sqlstr.Execute(sqlstr)

if rs.eof then exit sub

do while rs.eof = false
xx = rs.fileds(1).value
rs.movenext
loop

sqlstr = "update table1 set filter1 = 'hello'"
SqlConn.execute sqlstr 把这段代码的意思说出来，要一步一步的详细点的

Answer 1

Public SqlConn As ADODB.Connection //定义一个数据库连接SqlConn
On Error GoTo Handler //发生错误时跳转到 handler标签
Set SqlConn = New ADODB.Connection //实例化SqlConn
SqlConn.CursorLocation = adUseClient //不知道
ConnStr = "Provider=SQLOLEDB.1;Password=sa;Persist Security Info=True;User ID=sa;Data Source=myserver" //设置数据库连接信息字符串ConnStr
SqlConn.ConnectionString = ConnStr //设置Sqlconn的连接字符串为ConnStr
SqlConn.Open //打开连接

dim rs as adodb.recordset, sqlstr as string //定义rs为一个recordset类型（大概是记录容器吧）,sqlstr为一个字符串

sqlstr= "select * from table" //设置sqlstr的内容，其内容为操作数据库的语句select语句
set rs = Sqlstr.Execute(sqlstr) //设置rs的内容为sqlstr内所包含的操作数据库语句所返回的结果。。。。这里Sqlstr怎么突然冒出来的？中间丢东西了吧

if rs.eof then exit sub //如果返回结果集为空则推出本子程序

do while rs.eof = false //当返回结果集不到最后一条则一直做
xx = rs.fileds(1).value //设置xx为rs当前行的第一个列的值
rs.movenext //rs下一行
loop //循环

sqlstr = "update table1 set filter1 = 'hello'" //设置sqlstr为操作数据库语句，此次为update语句
SqlConn.execute sqlstr //执行此条语句

Answer 2

update table1 set filter1 = 'hello' 是一段SQL语言，意思是把table1
这张表里面所有的记录的filter值设置成‘hello’
SqlConn.execute sqlstr
意思就是执行上面这段sql文，执行完成后 table中的filter值都会变成‘hello’

Answer 3

十分就要一步一步详细点 说话的口气好象别人欠他一样 现在提问的都是爷了 连句谢谢都没 知道都不想告诉你