MDB file with t1, t2, t3, three data tables, this query to join a DateSet at the same time, can be yao, grammar is correct, test, can query to the results, beginners have what not understand, please teach the teacher, thank you!
Dim check_name As String
Dim check_file As String
Dim ado_con As OleDbConnection=New OleDbConnection
Dim ado_adater As New OleDbDataAdapter
Dim ado_builder As New OleDbCommandBuilder
Dim pDateset As New DataSet

Ado_con. The ConnectionString="provider=Microsoft. Jet. The oledb. 4.0; Data source="& amp; Check_file & amp; "\ test. The MDB"
Ado_con. The Open ()
Ado_builder. Dataadapters=ado_adater

Ado_adater. SelectCommand=New OleDbCommand (" the select * from t1, "ado_con)
Ado_adater. The Fill (pDateset, "t1")

Ado_adater. SelectCommand=New OleDbCommand (" the select * from t2, "ado_con)
Ado_adater. The Fill (pDateset, "t2")

Ado_adater. SelectCommand=New OleDbCommand (" the select * from t3, "ado_con)
Ado_adater. The Fill (pDateset, "t3")