E/SQL application development for library automation

We have HP Allbase SQL running on HP 9000 with MPE/iX operating system. Having knowledge of ESQL/C and relational database theory and schema design, I plan to write a library automation package for a library .

My questions are:
1) Has anyone attempted library automation using the standard DBMSs like ORACLE, SYBASE, INFORMIX, DB2, rdb, INGRES, etc. Most of the libraries seem to use packages supplied by some library automation vendors.

2) How does developing library automation package on top of a standard DBMS compare to buying one from a library automation vendor? Obviously buying one requires lot of money and developing one requires lot of time.

3) Is it preferable to develop ESQL/C applications on UNIX rather than non-UNIX environment?

4) Any comments about portability of ESQL/C code between various relational DBMSs ?

Any comments and experiences either in library automation or other relevant application development will be appreciated..

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Prasad  Polamraju				Phone: 703-328-0180 (office)
Math/Computer Science Dept				703-328-4245 (home)
Clinch Valley College of the Univ of Virginia
Wise VA 24293			email: rvp2f_at_virginia.edu or rvp2f_at_clinch.edu