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
- 187789 Views
- Banking, CMC, CTS, HCL, Infosys, Keggfarms, SkyEss, Sunrise, TCS, Web Synergies, Wipro, I also Faced
- E-Mail Answers
Answer Posted / fopal kanjolia
A Primary key is one or more columns in a table used to
uniquely identify each roe in the table primary key value
must not be null and must be unique across the columns
| Is This Answer Correct ? | 24 Yes | 24 No |
Post New Answer View All Answers
What is the difference between specialization and generalization?
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.
What is the use of default key?
Differentiate between extension & intension?
Data structure used to implements a menu:
define primary key index, bitmap index, hash index,virtual indwx
can i use the commands "modify" and Change in DB2 to alter my column datatype and its name in a table?
What do you mean by cluster and non cluster index?
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
How default key is different from primary key?
What is database collection?
What is database client?
Give the syntax of exception handling used in DBMS?
What will happen non-clustered index will be created on clustered index?
What are the types of joins?
