Thanks for both Jim and Larry to explain to me.

>Just a note to add to what Jim said. When the table is opened by the grid, it does not respect the BufferMode setting of the form. The table will be opened with no buffering at all.
>
>>I found the explanation of the RecordSourceType of a grid in VFP's help:
>>Table - Automatically opens the table specified in the RecordSource property setting.
>>Alias. Treats the record source as specified.
>>I have checked some books but still not understand what is their difference.
>>In my case, I filered a table at a form's Init then it shows my filter result of that table in my grid if I use "Alias" in the RecordSourceType.
>>But it shows all the records of that table if I use "Table" in the RecordSourceType.
>>Anyone can explain to me? Or give me some examples to show their difference?
>>
>>Thanks