1. M.P. Johnson, DBMS, Stern/NYU, Sp20041 C20.0046: Database Management Systems Lecture #17 Matthew P. Johnson Stern School of Business, NYU Spring, 2004

2. M.P. Johnson, DBMS, Stern/NYU, Sp2004 2 Agenda Previously: Pro*C, Midterm, break Next: Discuss midterm Project part 3 is up More programming for SQL  Embedded SQL Pro*C, SQLJ  PSMs  CLI SQL/CLI in C JDBC in Java DBI/DBDs in Perl PHP (HTML?)

3. M.P. Johnson, DBMS, Stern/NYU, Sp2004 3 First: Evals Speed Varying depth of coverage Grades One-minute responses

4. M.P. Johnson, DBMS, Stern/NYU, Sp2004 4 Recap: Embedded SQL Host language + Embedded SQL Preprocessor Host Language + function calls Host language compiler Executable Preprocessor Host language compiler Oracle’s Pro*C gcc prog.pc prog.c a.out

5. M.P. Johnson, DBMS, Stern/NYU, Sp2004 5 Embedded SQL/Pro*C Benefits? Problems? Solutions?

6. M.P. Johnson, DBMS, Stern/NYU, Sp2004 6 Interface: SQL/Host Language Two languages: SQL, host (C/Java/whatever) Benefits:  DB code (SQL is portable)  SQL, host language focus on own strengths SQL code placed in host language code SQL and host language have diff. data types  “impedance mismatch”  Data transferred with “shared variables” Use cursors to access/modify data Error messages placed in SQLSTATE

7. M.P. Johnson, DBMS, Stern/NYU, Sp2004 7 Recall: Pro*C on sales Example script: sample1.pc  See Pro*C tutorialPro*C tutorial Pro*C compiler is proc  Must include /oracle/precomp/public  Must link with shared library /oracle/lib/libclntsh.so  Includes makefile proc.mk, but may require modifications sales% cp /oracle/precomp/demo/proc/*.pc. sales% proc sample1.pc sales% gcc -I/oracle/precomp/public /oracle/lib/libclntsh.so -osample1 sample1.c sales% sample1 sales% cp /oracle/precomp/demo/proc/*.pc. sales% proc sample1.pc sales% gcc -I/oracle/precomp/public /oracle/lib/libclntsh.so -osample1 sample1.c sales% sample1

8. M.P. Johnson, DBMS, Stern/NYU, Sp2004 8 Embedded SQL example Example script: sample2.pc  See Pro*C tutorialPro*C tutorial Goal: display all salespeople  Use cursor to scroll through results sales% proc sample2.pc sales% gcc -I/oracle/precomp/public /oracle/lib/libclntsh.so –osample2 sample2.c sales% sample2 sales% proc sample2.pc sales% gcc -I/oracle/precomp/public /oracle/lib/libclntsh.so –osample2 sample2.c sales% sample2