Hi John ---

> 1. If my module is only involve a record at a time (e.g. create user record), am I going to use row buffering instead of table buffering?

You could use either. Some people like to always use table buffering. I would go with row buffering.

> 2. If I am using row buffering in my create\modify user module, how could I ensure the data is not conflict? using getfldstate()?

Yes, and also in your save routine, check CURVAL() and OLDVAL() to ensure that the data has not been changed by another.

> 3. When I use table buffering for those mudule that involve more than one record at a time, will the entire table be overwriiten by the buffered when TABLEUPDATE() issued?

No. Only those records changed. You could always use GETNEXTMODIFIED() to go record by record and update each record rather than the whole table. See the VFP documentation for some good examples of how to do this.

> 4. If I get that, there are changes made for other records as well by other users, and table bufeering seen will overwrite the entire table (if so), how to solve this problem in case the changes made by both side can be saved without need to re-key in or whatever things that will made users unhappy?

See above.

> 5. I found that, TASRADE from MS is using CONTROLSOURCE to link the field data to relevant control. When the form launched, the 1st record will be displayed automatically. How to avoid it happen (usually the controls are blank when user launch form for create user)? Append blank at the beginning? Set the controlsource only when save button press? Or any other solution?

Tastrade, IMHO, is crap. It's overly complicated and a very slow and cumbersome UI. What do you want to happen when the user launches a form? If you want to launch into a new record, by all means put an INSERT INTO or APPEND BLANK in the Init of the Form.