利用VB怎样做才算是一个好的查询？

[baiyunyi]

我在用VB做查询模块，不论怎么做总是不竟人意或出错。

[流梓]

可以用模糊查询。

[heipifeng]

你是怎么做的啊,代码贴出来看看

[strikerfy]

我最近做了个查询,不知道对你有没有用,查询作成模块的话,不好传参数,最好根据需求做一个好的界面,再根据界面做查询代码,不同类型字段在sql语句里的表达不一样,所以最后提交的sql语句要金国处理,我没有用中间表查询,用的是ACCESS数据库,如果我搞清楚的ADO连ACCESS代码如下:

Dim sTemp As String
Dim s1 As Variant
Dim OrAnd As String
'On Error GoTo Err
cmdprint.Enabled = True
'用ADO建立数据连接
If Combo1.Text = "" Or Combo2.Text = "" Then
MsgBox "请先选择要查询的库和表", , "警告"
Exit Sub
End If
If rs.State = adStateOpen Or db.State = adStateConnecting Then
rs.Close
db.Close
End If
db.ConnectionString = "Provider=Microsoft.Jet.OLEDB.3.51;Persist Security Info=False;Data Source=" _
& App.Path & sSetDBname & ";"
db.Open

'设置SQL查询串
'如果字段值为空，就默认为查找出所选库中所有的记录
If Text1.Text = "" Then
rsSql = "select * from " & sTable
Querytable = Combo2.Text
ShowData
Exit Sub
End If

'字段值不为空时
rsSql = "select * from " & sTable & " where"
s1 = Trim(Text1.Text)
sChoice1 = " " & Combo3.Text & logic4 & "'" & s1 & "'"
If Right$(Combo3.Text, 2) <> "时效" Or Right$(Combo3.Text, 2) <> "日期" Or Right$(Combo3.Text, 2) <> "利息" Or Right$(Combo3.Text, 2) <> "金额" Or Right$(Combo3.Text, 2) <> "利率" Then
If logic4 = "=" Then logic4 = "like"
sChoice1 = " " & Combo3.Text & " " & logic4 & " '" & s1 & "%'"
'MsgBox sChoice1
End If
Select Case Right$(Combo3.Text, 2)
Case "时效", "日期"
s1 = Text1.Text
If logic4 = "like" Then logic4 = "="
sChoice1 = " " & Combo3.Text & logic4 & "#" & s1 & "#"
Case "本金", "利息", "金额", "利率"
s1 = Text1.Text
If logic4 = "like" Then logic4 = "="
sChoice1 = " " & Combo3.Text & logic4 & s1
End Select
'一次查询
If Option1.Value = True Then
rsSql = rsSql & sChoice1
'MsgBox rsSql, vbExclamation, "一次性查询"
Querytable = Combo2.Text
ShowData
'Combo1.Text = ""
Combo2.Clear
Combo3.Clear
Combo4.Text = "等于"
Text1.Text = ""
Exit Sub
End If

'多次查询
If Option2.Value = True Then
If (Option3.Value = False) And (Option4.Value = False) Then
trsSql = rsSql & sChoice1
End If
If Option3.Value = True Then
OrAnd = " and"
trsSql = trsSql & OrAnd & sChoice1
End If

If Option4.Value = True Then
OrAnd = " or"
trsSql = trsSql & OrAnd & sChoice1
End If

rsSql = trsSql
'MsgBox rsSql, vbExclamation, "多次查询的SQL字符串"
ShowData
Option3.Enabled = True
Option4.Enabled = True
End If

Exit Sub
'Err:
' ShowErr

[remanwang]

具体一点

[lalalulu]

up

[baiyunyi]

If List2.ListCount = 0 Then
MsgBox "请选择查询条件!", 0 + 48, "查询提示"
Else
Dim Sqlstr As String
Dim Str1 As String: Dim i As Integer
For i = 0 To List2.ListCount - 1
List2.ListIndex = i
Str1 = Str1 & " " & List2.Text
Next i
Sqlstr = "select * from sq_hjb where" & " " & Str1
Adodc1.CommandType = adCmdText
Adodc1.RecordSource = Sqlstr
Set DataGrid1.DataSource = Adodc1
Adodc1.Refresh
DataGrid1.ReBind
Label2.Caption = Adodc1.Recordset.RecordCount
If Adodc1.Recordset.RecordCount > 0 Then
Label3.Visible = True
Label2.Visible = True
DataGrid1.Visible = True
HScroll1.Visible = True
Else
Label3.Visible = False
Label2.Visible = False
DataGrid1.Visible = False
HScroll1.Visible = False
End If
End If



这是我的查询，

strikerfy(胖茄子) 谢谢你，你的程序对我很有帮助。