CSCI235/CSCI835 Database Systems Assignment 1 5 August 2018

Transcription

1 School of Computing and Information Technology Session: Spring 2018 University of Wollongong Lecturer: Janusz R. Getta CSCI235/CSCI835 Database Systems Assignment 1 5 August 2018 Scope This assignment includes the tasks related to normalization of relational schemas, implementation of data retrieval in PL/SQL and implementation of stored procedures and functions in PL/SQL. The outcomes of the laboratory work are due by Saturday 25 August, 2018, 7.00 pm (sharp). Please read very carefully information listed below. This laboratory contributes to 10% of the total evaluation in a subject CSCI235 and it contributes to 6% of the total evaluation in a subject CSCI835. A submission procedure is explained at the end of specification. This assignment consists of 4 tasks and specification of each task starts from a new page. It is recommended to solve the problems before attending the laboratory classes in order to efficiently use supervised laboratory time. A submission marked by Moodle as "late" is treated as a late submission no matter how many seconds it is late. A policy regarding late submissions is included in the subject outline. A submission of compressed files (zipped, gzipped, rared, tared, 7-zipped, lhzed, etc) is not allowed. The compressed files will not be evaluated. All files left on Moodle in a state "Draft(not submitted)" will not be evaluated. An implementation that does not compile due to one or more syntactical errors scores no marks. It is expected that all tasks included within Assignment 1 will be solved individually without any cooperation with the other students. If you have any doubts, questions, etc. please consult your lecturer or tutor during lab classes or office hours. Plagiarism will result in a FAIL grade being recorded for the assessment task.

2 Prologue Download the files dbcreate.sql and dbdrop.sql included in a section SAMPLE DATABASE. To drop a sample database, process a script dbdrop.sql. To create a sample database, process as script dbcreate.sql. It is strongly recommended to drop a sample database and to re-create it before each implementation task. No report is expected from Prologue. Tasks Task 1 (3 marks) Read the following specification of a sample database domain. A hospital would like to create a medical database with the health records of its patients. Information recorded in the database supposed to include a medical insurance number that identifies each patient, first name, last name, a list of admission dates to the hospital, list of illnesses cured during each admission, and a list of children. Assume, that more than one illness can be cured during each admission to the hospital. Also assume, that a child is described by the first name and a type of relation to its parent, i.e. either son or daughter. A database designer created the following relational schema. MRECORD(insurance,fname,lname,adate,illness,child,relation) Determine what the highest valid normal form a relational schema MRECORD is in? Justify your choice. Your next task is to decompose the relational schema into the smallest number of relational schemas each one in 4NF and to prove that each schema is in 4NF. To prove, that the relational schemas obtained from the decomposition are in 4NF you must find all functional and multivalued dependencies valid in each relational schema, you must find the minimal keys, and then apply the definitions. Note, that a relational schema is in 4NF when it is in BCNF and it does not have any nontrivial multivalued dependencies. It means, that first, you have to prove that a schema is in BCNF and later show that it has no nontrivial multivalued dependencies. Please keep in mind that the smallest number of 4NF relational schemas is expected. Deliverables A file solution1.pdf with an identification of the highest valid normal form a relational schema MRECORD is in and a justification your decision. Then, a file solution1.pdf must also contain a list of the relational schemas obtained from the decompositions. Each relational schema must have a list of nontrivial functional and/or

3 multivalued dependencies valid in the schema attached, and a justification why the schema is in 4NF.

4 Task 2 (2 marks) Implement an anonymous PL/SQL block that lists the employee number, driver licence number, and full name of all drivers who performed at least one trip in To extract a year from a value of attribute TRIP_DATE of type DATE you can use a row function TO_CHAR(TRIP_DATE,'YYYY'). To list information retrieved from a sample database use PL/SQL package DBMS_OUTPUT. It is explained in the Cookbook, Recipe 7.1 How to start programming in PL/SQL how to use DBMS_OUTPUT package. Remember about SET SERVEROUTPUT ON at the beginning of a script file that contains your anonymous PL/SQL block. Information about the drivers must be listed in the following format. EMPLOYE#: 777 LICENCE#: 007 NAME: James Bond ================================ EMPLOYE#: 666 LICENCE#: 006 NAME: Harry Potter ================================ and so on. When a database does not contain information about the drivers who performed at least one trip in 1995 the following message must be displayed. No drivers performed a trip in Your implementation must use at least one cursor and at least one exception handler. In fact, such constraints make your implementation easier. To test your solution put an implemented anonymous PL/SQL block into SQL script file solution2.sql and process the script twice. First, test your solution for an initial state of a sample database where at least one driver performed a trip in Next test your solution for an updated state of a sample database where no drivers performed a trip in Then, merge the reports from both tests into a file solution2.lst. Your report must include a listing of all PL/SQL statements processed. To achieve that put the following SQL*Plus commands: SPOOL file-name SET ECHO ON SET FEEDBACK ON SET LINESIZE 100 SET PAGESIZE 200

5 SET SERVEROUTPUT ON at the beginning of SQL script and SPOOL OFF at the end of SQL script. Deliverables A file solution2.lst with a report from testing of an anonymous PL/SQL block implemented in this task. A report must have no errors and it must list all PL/SQL and SQL statements processed.

6 Task 3 (2 marks) Implement a stored PL/SQL procedure INSERT_TRIPLEG(trip_number,leg_number,departure,destination) that inserts a row into a relational table TRIPLEG and it also enforces the following consistency constraint on data entry into a relational table TRIPLEG. For all trip legs that belong to the same trip and such that leg_number > n where n > 1 a value of departure attribute must be equal to a value of destination attribute in a trip leg where leg_number = n-1. It means that for all trip legs except the first one a departure location must be the same as a destination location of the previous trip leg. To simplify the problem, assume that the rows are inserted into a relational table TRIPLEG in the increasing order of an attribute leg_number and that a row where a value of attribute leg_number = n is immediately followed by a row where a value of attribute leg_number = n + 1. If the consistency constraint is satisfied insert and commit a row in TRIPLEG table. Otherwise, use DBMS_OUTPUT PL/SQL package to display an error message when the consistency constraint is violated and do not insert a row. When INSERT_TRIPLEG procedure is ready create SQL script solution3.sql that stores the procedure in a data dictionary and tests the procedure with EXECUTE statements. Insert at least two new trip legs where the consistency constraint is satisfied and at least one new trip leg where the consistency constraint is violated. A good idea is to create a new trip first. Process SQL script solution3.sql and save a report from processing in a file solution3.lst. Your report must include a listing of all PL/SQL statements processed. To achieve that put the following SQL*Plus commands: SPOOL file-name SET ECHO ON SET FEEDBACK ON SET LINESIZE 100 SET PAGESIZE 200 SET SERVEROUTPUT ON at the beginning of SQL script and SPOOL OFF

7 at the end of SQL script. Deliverables A file solution3.lst with a report from processing of SQL script solution3.sql. A report must have no errors and it must list all PL/SQL and SQL statements processed.

8 Task 4 (3.0 marks) Implement a stored PL/SQL function CVISITED(trip_number) that returns the names of all cities visited by a driver while performing a trip with a given trip number determined by a value of parameter trip_number. The names of the cities visited during a trip must be returned as a string of city names separated with ', ' (comma followed by a blank). For example, Sydney, Adelaide, Dapto, Melbourne The names of the cities must be listed in the same order as the order in which the cities have been visited during a trip and the intermediate stops must be listed only once. If a value of parameter trip_number is incorrect then the function must return NULL. When ready, implement a script solution4.sql that stores the function in a data dictionary and tests a function. To test a function implement SELECT statements that lists all cities passed by a given driver (a driver is up to you) during each one of the trips performed by a driver. Remember to also test a special case when a driver performed no trips so far. Process SQL script solution4.sql and save a report from processing in a file solution4.lst. Your report must include a listing of all PL/SQL statements processed. To achieve that put the following SQL*Plus commands: SPOOL file-name SET ECHO ON SET FEEDBACK ON SET LINESIZE 100 SET PAGESIZE 200 SET SERVEROUTPUT ON at the beginning of SQL script and SPOOL OFF at the end of SQL script.

9 Deliverables A file solution4.lst with a report from processing of SQL script solution4.sql. A report must have no errors and it must list all PL/SQL and SQL statements processed.

10 Submission Submit the files solution1.pdf, solution2.lst, solution3.lst, and solution4.lst through Moodle in the following way: (1) Access Moodle at (2) To login use a Login link located in the right upper corner the Web page or in the middle of the bottom of the Web page (3) When logged select a site CSCI835/CSCI235 (S218) Database Systems (4) Scroll down to a section SUBMISSIONS (5) Click at a link In this place you can submit the outcomes of Assignment 1 (6) Click at a button Add Submission (7) Move a file solution1.pdf into an area You can drag and drop files here to add them. You can also use a link Add (8) Repeat a step (7) for the files solution2.lst, solution3.lst, and solution4.lst. (9) Click at a button Save changes (10) Click at a button Submit assignment (11) Click at the checkbox with a text attached: By checking this box, I confirm that this submission is my own work, in order to confirm the authorship of your submission. (12) Click at a button Continue End of specification