>>>I wonder how do you handle the RI in VFP. VFP have a mechanism for RI. However, when I test it, I feel it is very restricted. Does VFP have complete functions for accessing the RI rules in a defined database (*.dbc)?
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>>Yes, it has. Look at DBGetProp table properties.
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>DBGetProp does not seem to tell you the relationship among the tables. How can I find what is the relationship (master-detail) among the tables in a form, what are the link fields, what are the rules for deletion, changing key, etc. in run time?

You can run the GENDBC program which will give you a text file describing every table in your DBC and their relations. Or, you can use the Modify command for the DBC (in your project manager) and see a graphical representation of the relationships. Right-click on this screen and you will get a menu showing more detailed information

HTH
Barbara