参数类型（常用）：
adBoolean 11 (bit)
adTinyInt 16
adSmallInt 2
adInteger 3
adSingle 4
adDouble 5
adNumeric 131
adVarChar 200 (varchar)
adLongVarChar 201 (text)
adVarWChar 202 (nvarchar)
adLongVarWChar 203 (ntext)
adVarBinary 204
adLongVarBinary 205
adDateTime 135
adCurrency 6
