MSSQL:
	sysforeignkeys
		constid = foreign key name
		fkeyid = the table IN WHICH constraint is placed (A-table)
		rkeyid = the table TO WHICH constraint point out (B-table)
		fkey = column index in A-table
		rkey = column index in B-table

	sysobjects
		name = name of object
		id = id of object
		xtype = type of object (U - user table, V - view, F - foreign key, P - primary key)

	syscolumns
		id = id of sysobject (table)
		name = column name
		colid = column index