CS 430/630                                                      E. O'Neil
		      Homework Assignment 4
due Sun., Nov. 15

Exercises to turn in:  5.1 (try out the supplied program), 5.3, 
5.4, 5.5, 5.6, 5.7, 5.8, 5.11.  
Note that 5.5 and 5.6 are the longest as programs, so you might
want to do them last.  Problem 5.6 is important as an example of
a nontrivial transactional program.  Problem 5.7(a) is postulating
a program with the same single-row updates but they are not
contained in a *transaction*.  You don't need to code up 5.7(c),
just discuss it with a snippet of code.

Note on 5.7a: The setup here is like auto-commit: each update
is separately committed.  Note that nothing is *reading* here,
but in part b, a reader is involved.

You can use C or Java:

C support:
Note that the prompt() function mentioned in Chap. 5 and Appendix B
is provided in the esql directory linked from the class web page,
in files, prompt.pc and prompt.h. There is also a 
makefile for compiling your source using the ORACLE precompiler and
the support libraries, on host dbs2.  First try it out on ex511.pc,
also in directory esql using "make E=ex511" with no spaces around
the = sign.

Java support:
See examples in the jdbc directory linked from the class web page,
and the makefile there. First try it out on Ex511.java,
also in directory esql using "make E=Ex511" with no spaces around
the = sign.

Oracle errors (C or Java)
If you need to interpret an ORACLE error number, try out the Oracle
tool (i.e. UNIX program) "oerr."  If you see "ORA-00122", for example,
you type the following at the UNIX prompt:
  oerr ora 122
and see its error string.  You can get these error strings using your
own coding--see ex511.pc or Ex511.java and try it out by using a
bad user name on connection.

Delivery

For each program, make a script showing that it works for 3-6 user 
interactions, (all in one run of the program) and leave it as a 
.script file with the name specified below.

To make a script file, run the UNIX program "script" before running your 
program and simply do an "exit" command after it, like this:

% script ex1.script
% ex1.ox         or make E=Ex1 for Java
...   <interact with program, finally making it exit>
% exit                

Files we will collect:
ex1.pc or Ex1.java, ex1.script for 5.1
ex3.pc or Ex3.java, ex3.script for 5.3
ex4.pc or Ex4.java, ex4.script for 5.4
agents.pc or Agents.java, agents.script for 5.5a
orders.pc or Orders.java, orders.script for 5.6a
getord.pc or GetOrd.java, getord.script for 5.6b
median.pc or Median.java, median.script for 5.8
managers.pc or Managers.java, managers.script for 5.11

hw5answers.txt for 5.5b, 5.6c, 5.6d, 5.7

Please use the right names, including case, so our collection script
works!