主题：请教效率

下面的语句如何优化

Dim st As Date = Date.Now

Dim mc As String

For Each c As DataCol In DataTables("dtpzzbwb").DataCols

    If c.IsString = True Then

        mc = c.name

        Dim cmd As New SQLCommand

        Dim nm As Integer

        cmd.C

        cmd.CommandText ="Select Count(*) Fr  om {dtpzzbwb} Where " & mc & "  = '" & "查找的字符" & "'"

        nm = cmd.ExecuteScalar

        Output.Show(c.name & "-" & nm)

    End If

Next