
Primary Key:
A Primary Key in a
Example:
Students in Universities are assigned a unique registration number.
Therefore, in a STUDENT database table, the attribute “reg_no” acts as primary key.
Foreign Key:
Foreign Key is a column in a relational database table which provides a relation between two tables. It provides a cross reference between tables by pointing to primary key of another table.
Example:
In STUDENT database table, the attribute “reg_no” acts as primary key and in COURSE database table in which the student selects his or her course, the same “reg_no” acts as foreign key for the STUDENT table.
Many to One Relationship:
When more than one record in a database table is associated with only one record in another table, the relationship between the two tables is referred as many to one relationship. It is also represented as M: 1 relationship.
One to Many Relationship:
When one record in a database table is associated with more than one record in another table, the relationship between the two tables is referred as one to many relationship. It is also represented as1: M relationship. This is the opposite of many to one relationship.
CROW FOOT ERD:
The Crow Foot ERD is an Entity Relationship Diagram which is used to represent the cardinalities present in the basic ER diagram. It is used to represent the relationships present between two tuples or tables present in the database.

Trending nowThis is a popular solution!

Chapter 3 Solutions
EBK DATABASE SYSTEMS: DESIGN, IMPLEMENT
- Please answer both Exercise 1 and2(these questions are not GRADED)arrow_forwardDiscussion 1. Comment on your results. 2. Compare between the practical and theoretical results. 3. Find VB, Vc on the figure below: 3V V₁₁ R₁ B IR, R, IR, R www ΙΚΩ www www I 1.5KQ 18₁ 82002 R₁ 3.3KQ R₂ 2.2KQ E Darrow_forwardAgile1. a. Describe it and how it differs from other SDLC approachesb. List and describe the two primary terms for the agile processc. What are the three activities in the Construction phasearrow_forward
- how are youarrow_forwardneed help with thi Next, you are going to combine everything you've learned about HTML and CSS to make a static site portfolio piece. The page should first introduce yourself. The content is up to you, but should include a variety of HTML elements, not just text. This should be followed by an online (HTML-ified) version of your CV (Resume). The following is a minimum list of requirements you should have across all your content: Both pages should start with a CSS reset (imported into your CSS, not included in your HTML) Semantic use of HTML5 sectioning elements for page structure A variety other semantic HTML elements Meaningful use of Grid, Flexbox and the Box Model as appropriate for different layout components A table An image Good use of CSS Custom Properties (variables) Non-trivial use of CSS animation Use of pseudeo elements An accessible colour palette Use of media queries The focus of this course is development, not design. However, being able to replicate a provided design…arrow_forwardUsing the notationarrow_forward
- you can select multipy optionsarrow_forwardFor each of the following, decide whether the claim is True or False and select the True ones: Suppose we discover that the 3SAT can be solved in worst-case cubic time. Then it would mean that all problems in NP can also be solved in cubic time. If a problem can be solved using Dynamic Programming, then it is not NP-complete. Suppose X and Y are two NP-complete problems. Then, there must be a polynomial-time reduction from X to Y and also one from Y to X.arrow_forwardMaximum Independent Set problem is known to be NP-Complete. Suppose we have a graph G in which the maximum degree of each node is some constant c. Then, is the following greedy algorithm guaranteed to find an independent set whose size is within a constant factor of the optimal? 1) Initialize S = empty 2) Arbitrarily pick a vertex v, add v to S delete v and its neighbors from G 3) Repeat step 2 until G is empty Return S Yes Noarrow_forward
- Database Systems: Design, Implementation, & Manag...Computer ScienceISBN:9781305627482Author:Carlos Coronel, Steven MorrisPublisher:Cengage LearningDatabase Systems: Design, Implementation, & Manag...Computer ScienceISBN:9781285196145Author:Steven, Steven Morris, Carlos Coronel, Carlos, Coronel, Carlos; Morris, Carlos Coronel and Steven Morris, Carlos Coronel; Steven Morris, Steven Morris; Carlos CoronelPublisher:Cengage Learning
- A Guide to SQLComputer ScienceISBN:9781111527273Author:Philip J. PrattPublisher:Course Technology PtrEnhanced Discovering Computers 2017 (Shelly Cashm...Computer ScienceISBN:9781305657458Author:Misty E. Vermaat, Susan L. Sebok, Steven M. Freund, Mark Frydenberg, Jennifer T. CampbellPublisher:Cengage LearningNp Ms Office 365/Excel 2016 I NtermedComputer ScienceISBN:9781337508841Author:CareyPublisher:Cengage




