用数据库生成不重复的流水号-小叶白龙博客

‘函数名：getMaxOrder
‘作用：得到最大序列号
‘参数：fieldName   —-在序列号表中的字段名
‘        tableName   —-序列号所在表名
‘        fieldName   —-在表中的字段名
‘返回值：字段的最大值
‘调用函数：idAdd：作用见上
‘*************************************************
function getMaxOrder(fieldName,tableName,tableFileName)
dim orderNO,orderRS,testRS
set testRS=Server.CreateObject("ADODB.recordset")
set orderRS=Server.CreateObject("ADODB.recordset")
firstNO=year(date)&right(("0"&month(date)),2)
orderSQL="select * from fieldMaxValue where fieldName=’"&fieldName&"’"
orderRS.open orderSQL,conn,3,2
if not orderRS.eof then
  orderRS("fieldMaxValue")=orderRS("fieldMaxValue")
  orderNO=orderRS("fieldMaxValue")
  if left(orderNO,6)=firstNO then
   orderNO=idAdd(orderNO)
  else
   orderNO=firstNO&"00001"
  end if
else
  orderRS.addnew
  orderRS("fieldName")=fieldName
  orderNO=firstNO&"00001"
end if
testRS.open "select max("&tableFileName&") from "&tableName&" where "&tableFileName&" like ‘"&firstNO&"%’",conn,1,2
if (not testRS.eof) and testRS(0).value>orderNO then
  orderNO=idAdd(testRS(0).value)
end if
testRS.close
set testRS=nothing
orderRS("fieldMaxValue")=orderNO
orderRS.update
orderRS.close
set orderRS=nothing
getMaxOrder=orderNO
end function

‘*************************************************
‘函数名：idAdd
‘作用：用来增加一：比如idAdd("5")="6",idAdd("L99")="M00"，idAdd("!")="!1"
‘                如果是数字就到9后进位,如果是小写字母到期z后进位
‘                如果是大写字母到Z后进位，其它在后面加一个1
‘参数：id   —-需来增加的数
‘返回值：增加后的数
‘调用函数：addOne 一个数增加一 AddOne("5")="6",Add(9)="0",AddOne("a")="b",
‘                              AddOne("z")="a",AddOne("A")="B",AddOne("Z")="A"
‘*************************************************
Function AddOne(first)
Dim tempfirst
AddOne = first
intfirst = Asc(first)
If (intfirst >= 48 And intfirst < 57) Or (intfirst >= 65 And intfirst < 90) Or (intfirst >= 97 And intfirst < 122) Then
    AddOne = Chr(intfirst + 1)
    Exit Function
End If
If (intfirst = 57) Then
    AddOne = "0"
    Exit Function
End If
If (intfirst = 90) Then
    AddOne = "A"
    Exit Function
End If
If (intfirst = 122) Then
    AddOne = "a"
    Exit Function
End If
End Function

Function idAdd(id)
Dim fornt, back, strFind, strBackFind, idLen, tempid
if id="" or isNull(id) then
iddAdd=1
exit Function
end if
tempid = id
idLen = Len(id)
For i = 1 To idLen
    fornt = Left(id, idLen – i)
    back = Right(id, i – 1)
    strFind = Mid(id, idLen + 1 – i, 1)
    strBackFind = AddOne(strFind)
    id = fornt & strBackFind & back
    If strFind < strBackFind Then
        Exit For
    End If
    If strFind > strBackFind Then
        If i = idLen Then
            id = id & "1"
        Else
            If Mid(id, idLen – i, 1) = AddOne(Mid(id, idLen – i, 1)) Then
                id = fornt & strBackFind & back & "1"
                Exit For
            End If
        End If
    End If
Next
If id = tempid Then
    id = id & "1"
End If
idAdd = id
End Function