Question

In: Computer Science

Given Codd's Rule 4: Rule 4: Dynamic online catalog based on the relational model: The database...

Given Codd's Rule 4:

Rule 4: Dynamic online catalog based on the relational model: The database description is represented at the logical level in the same way as ordinary data, so that authorized users can apply the same relational language to its interrogation as they apply to the regular data.

In three sentences, explain what this means. Give two example queries from MySQL that show how MySQL realizes the concepts

Solutions

Expert Solution

Meaning of the rule :

This rule simply means that Description of actual database should be similarly represented as we represent ordinary data( by tables, columns, views etc). you must be able to inquire about a database's meta-data using the same language that you use to inquire about the actual data. What tables are available? What columns do they contain? Such questions can be answered.

Database dictionary(catalog) is called the Catalog. Dynamic nature of Database is called dynamic online catalog. Thsi rule simply says that Management of dynamic database should be in threlational model. The structure description of the complete Database and it must be stored online. The Catalog must be governed by same rules as rest of the database. The same query language should be used on catalog as used to query database.

Give two example queries from MySQL that show how MySQL realizes the concepts:

MySQL does have system tables in a special database called "mysql", that contain access privilege information and
are used to authenticate users and determine what tables, databases, and columns they have privileges on and what type of privileges they have.
You can find more information here. https://dev.mysql.com/doc/refman/5.7/en/system-schema.html

Note : You must be logged in as root inorder to execute the below statement.

Get the current Timezone used by MySQL database

SELECT @@GLOBAL.time_zone, @@SESSION.time_zone;


Display the current structure of the log tables

SHOW CREATE TABLE mysql.general_log;


Related Solutions

Data Modeling and Database Design (Database Concepts, Eighth Edition) The relational model is the most important...
Data Modeling and Database Design (Database Concepts, Eighth Edition) The relational model is the most important standard in database processing today. Why do you feel that this model has continued to be successful in the world of IT? What would happen if large corporations decided to reject this theory, and store their data using a non-relational model? Are there any success stories where this has happened?
Normalizing the Relational Model for the Student Project and Creating a Normalized SQL Database Patient (patientNo,...
Normalizing the Relational Model for the Student Project and Creating a Normalized SQL Database Patient (patientNo, name, address, phone, dateOfBirth, sex, insuranceCo, policyNo, relationshipToInsured) Appointment(patientNo, apptdate, appttime, reason, staffNo, visitNo) Visit(visitNo, patientNo, visitdate, visittime, duration, reason, visitType, visitCost, staffNo, roomNo) Staff(staffNo, name, title, specialty, address, phone) Availability(staffNo, availDate, startTime, endTime) InsurancePolicy (company, policyNo, insuredName, policytype, medicalCoPay, labCoPay, pharmacyCoPay, startDate, endingDate) DiagnosisMenu(diagCode, diagName) ProcedureMenu(procCode, procName, cost) Room(roomNo, roomType, condition) PrescriptionScript(scriptNo, visitNo, dateWritten, itemPrescribed, quantityPrescribed, directions, numberRefills) LabTest(testNo, prescriptionNo, testype, testDate, testTime,...
Case Study 4 A relational database is to be designed for a medium sized Company dealing...
Case Study 4 A relational database is to be designed for a medium sized Company dealing with industrial applications of computers. The Company delivers various products to its customers ranging from a single application program through to complete installation of hardware with customized software. The Company employs various experts, consultants and supporting staff. All personnel are employed on long‐ term basis, i.e. there is no short‐term or temporary staff. Although the Company is somehow structured for administrative purposes (that is,...
Part #4: Data normalization: Background: Data in a relational database is stored in a normalized form....
Part #4: Data normalization: Background: Data in a relational database is stored in a normalized form. Data normalization or just normalization is a strategy used to organize data into multiple related tables to reduce data redundancy while preserving data integrity. Exercise: Normalize the student data in the University table (sample data is shown further below) into 3 tables, namely, Student, Department, and Course. You do not need to populate data. Just illustrate the schema for the 3 tables. You may...
Given a relational database that consists of the following relations: Performer (pid: integer, pname: string, years_of_experience:...
Given a relational database that consists of the following relations: Performer (pid: integer, pname: string, years_of_experience: integer, age: integer) Movie (mname: string, genre: string, minutes: integer, release_year: integer, did: integer) Acted (pid: integer, mname: string) Director (did: integer, dname: string, earnings: real) Do the following using your Azure SQL database: a) Use SQL statements to create the relations. b) Populate the relations using SQL statements with the given data posted on Canvas. c) Implement the SQL queries for the following:...
Listed below is the relational database schema for an online store(SQL/Java): MEMBER(last_name, first_name, email, password, user,street,...
Listed below is the relational database schema for an online store(SQL/Java): MEMBER(last_name, first_name, email, password, user,street, city, state, zip, card_type, card_no, expiration, name_on_card) book_SALE(listing_no, seller, isbn, condition, price) ORDERS(order_no, buyer, order_date, tot) ITEM(order_no, listing_no) BOOK(isbn, title, author, edition, publisher, keywords) The bold attribute(s) in a relation is the primary key of that relation. The italized attributes in some relations denote foreign keys. The seller attribute in the book_SALE relation is a foreign key to the user attribute in the MEMBER...
Listed below is the relational database schema for an online store(SQL/Java): MEMBER(last_name, first_name, email, password, user,street,...
Listed below is the relational database schema for an online store(SQL/Java): MEMBER(last_name, first_name, email, password, user,street, city, state, zip, card_type, card_no, expiration, name_on_card) book_SALE(listing_no, seller, isbn, condition, price) ORDERS(order_no, buyer, order_date, tot) ITEMS(order_no, listing_no) BOOK(isbn, title, author, edition, publisher, keywords) The bold attribute(s) in a relation is the primary key of that relation. The italized attributes in some relations denote foreign keys. Create/Define the table.
Using the South University Online Library or the Internet, research database security and UML. Based on...
Using the South University Online Library or the Internet, research database security and UML. Based on your research and readings for the week, respond to the following discussion topics. Often, systems have only one level of security when it comes to databases. Imagine that someone is trying to add a name (which should be composed only of letters) to a database. The user mistakenly hits a number, and the system rejects the entry. Such security can be implemented at the...
4. How dynamic is the industry in which your company is based? Is there evidence that...
4. How dynamic is the industry in which your company is based? Is there evidence that industry structure is reshaping competition or has done so in the recent past? My company is TESLA
Rule Based System 1. Given the rule following rules from the class notes on production rules...
Rule Based System 1. Given the rule following rules from the class notes on production rules to convert an Arabic number less than 40 to a roman numeral. USING LOGIC Rule 1: if x is null then prompt the user and read x Rule 2: if x is higher than 999 then print “too Big” and make x null Rule 3: if x is between 10 and 39 then print “X” and reduce x by 10 Rule 4: if x...
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT