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Reconsider the situation described for Exercise 2.26 under the assumption that one bank is in the United States and the other is in Canada. As before, the banks use the schema of Figure 2.22, except that the Canadian bank uses the social-insurance number assigned by the Canadian government,whereas the U.S. bank uses the social-security number to identify customers.What problems (be- yond those identified in Exercise 2.24) might occur in this multinational case? How would you resolve them? Be sure to consider both the scheme and the ac- tual data values in constructing your answer | Database Concepts presented by Tim Haithcoat University of Missouri Columbia Introduction Very early attempts to build GIS began from scratch using limited tools like operating systems compilers More recently GIS have been built around existing lỆdatabase management systems DBMS P I - purchase or lease of the DBMS is a major part of the system s software cost -A -tthe DBMS handles many functions which would otherwiseipl VAVhave to be programmed into the GISt-pAi A ljV.AViA yAhjVp Any DBMS makes assumptions about the data which it andle W- -mi vẠA.Vp to make effective use of a DBMS it is necessary to fit those assumptions - certain types of DBMS are more suitable for GIS than others B because their assumptions fit spatial data better 2 Two ways to use DBMS within a GIS Total DBMS solution - all data are accessed through the DBMS so must fit the assumptions imposed by the DBMS designerm Mixed solution - some data usually attribute tables and Blrelationships are accessed through the DBMS lỆbecause they fit the model wellg Jt - some data usually locational are accessed directly because they do not fit the DBMS model
