vb access数据库数据同行两列数据如果相同,将相同的数字写入同行另一列?请高手赐教代码！

字段1 字段2 字段3
2 2

当字段1和字段2相同时，将2写入字段3中

当字段1和字段2相同时，将相同的数字2写入字段3中

update tablename set 字段3=字段1 where 字段1=字段2

dim conn as new adodb.connection dim rs as new adodb.recordset dim pstr as string dim dataname as string

private sub command3_click() dataname = "date.mdb路径" pstr = "provider=microsoft.jet.oledb.4.0;" & "data source=" & dataname conn.open pstr rs.cursorlocation = aduseclient rs.open "xpress", conn, adopenkeyset, adlockpessimistic rs.move(2)

rs.fields(3) = text1

rs.move(3)

rs.fields(3) = text2

end sub