Hi Irwan,

1 - how is the diffrent using engine in vfp against engine in sql server ?

Well in many ways. I shall cover only some of them:

a) Data security: VFP tables do not have a software based mechanisim to enforce security on tables. Any one with the proper permissions on the file server could simply access the data folder where your tables are stored and could copy, delete or modifiy the data of your app.

SQL Server uses software (a service) which is responsible for all the data managment (update,delete,insert,recover,etc) of the data stored in the databse files. In order for someone to have access to the data, he/she must establish a connection with the server by specifying a username/password wich has certain privleges and a set of tables and databases that he/she can/can not access.

b) Scalability: When your access VFP data (tables) your app/OS needs to send a low-level file access instructions to the file server requesting a file handle to the DBF you wish to use. This process is very inefficent because in order to access some of the data (probably just one customer record), you need to retrieve the entire DBF file, at least once. Imagine 90 users trying to access a 1.1 GB DBF File concurrenty, or even a worse senario could be trying to access this file via a small bandwith connection (like a modem).

SQL Server solves this problem by recieving commands (strings containing the instructions we wish the server to execute) from your app, and by sending back to your app only as much data as requested. That way if your app tell the server to send you the record for custommer NO. 1164, the server shall only send this record which could be 5KB long. This way you may have thousands of users connected to your database sending data back and forth over the wire without saturating your network.

This is the reason why VFP apps using VFP Tables is only recomended for applications with small to mid size requierments (No. users,data files sizes, etc).


c) Cost's : Performance for your app can be improved just by upgrading the hardware for the machine in which your database server is running, insted of having to upgrade all of your client computers and having to buy expensive network technology.



> 2. what application should i combine with vfp for manage large data ?

You could use ADO (Active Data Objects) for this.




>> hi all,
> i've 20 workstation and 1 server in my office, i've plant to use vfp for making application that good performace in index,seaching etc.
i've few question

1. how is the diffrent using engine in vfp against engine in sql server ?
2. what application should i combine with vfp for manage large data ?

thank's