VB查询语句!急！急！（在线。。。。）

[Alex.Ho]

Dim tab1 As String
Dim tab2 As String
Dim tab3 As String
Dim sql As String
Dim tabString As ADODB.Recordset

Private Sub Command1_Click()
Adodc.RecordSource = sql
adoad.Refresh
DataGrid.DataSource = Adodc
End Sub

Private Sub Command3_Click()
If Combo1.Text <> "" And Combo2.Text <> "" And Text3.Text <> "" Then
tab1 = Combo1.Text
tab2 = Combo2.Text
tab3 = Text3.Text
sql = "Select * From Empleror Where" & " " & tab1 & tab2 & tab3
Text2.Text = sql
End If
End Sub
其中Command3_Click用于生成查询语句条件，Command1_Click()为“查询按钮”，请问错在那里，请写出代码？