Interested to Buy Any Domain ? << Click Here >> for more details...
what is primary key,unique key, foreign key? can u teach me
in simple language?
- 44 Answers
- 187525 Views
- Banking, CMC, CTS, HCL, Infosys, Keggfarms, SkyEss, Sunrise, TCS, Web Synergies, Wipro, I also Faced
- E-Mail Answers
Answer Posted / inderjeet yadav
Primary key:A key which is uniquely indetified a row in a
table and primary key can not be null.
Unique key: A key which is uniquely indetified a row in a
table and but unique key can be null.
Foreign:Primary key of the first table that refering in
second table is know as foreign of second table.
| Is This Answer Correct ? | 3 Yes | 0 No |
Post New Answer View All Answers
What is difference between data and database?
What is database bounce?
What is ole db in ssis?
I have single column in a file. Input 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15 my output is file 1 have 1,2,3,10,11,12 file 2 have 4,5,6,13,14,15 and file 3 have 7,8,9 how is it possible in datastage
WHAT IS THE PURPOSE OF TESTING INTEGRITY OF THE UNIVERSE?
What is the function of cluster index?
Is it good to store images in database?
what is the full procedure for using store procedure in informatica7.1?
Which Statement would you use to remove the EMPLOYEE_Id_PK PRIMARY KEY constraint and all depending constraints from the EMPLOYEE table?
What is a Transformation?
london school of science and technology has a software development unit,known as lsst solutions,which is responsible for developing and implementing software throughout the collegejames tristan keeps a record of all student details in the college including student id,name,and start date and phone number.There are many courses offered by LSST. For example MBA, MSc, BSc, BABS, DF, English etc. Each course id identified by course id, description, duration. Each course has many semesters. Each semester takes place during a particular term. Semester details and term details are required to be stored in the database. Each course has many subjects and same subject may be offered in many courses. For each subject many details such as Subject code, name, result and attendance are required to be stored. Every subject has mainly two assessments; one assignment and one exam. Assignment is worth of 30% and exam 70% respectively. You have been appointed as a database designer. Your job is to provide ERD with all possible entities and relationships. Note: Feel free to make necessary assumptions 3: Assignment Tasks. 1. Create an ERD for the above problem 2. Translate the ERD to Relational Data model (RDM) 3. Implement the RDM by creating the tables 4. Populate the database with your own data. 5. SQL Queries for the following tasks a. List all student details in each course along with course details b. Count and display number of students in each course. c. List student name, course name, assessment description, marks for all students.
how can we view column head in first page but not in remaining pages?
Is data lake a database?
define primary key index, bitmap index, hash index,virtual indwx
What is the purpose of TNS?
