Normalization Practice Exercise | Third Normal Form| Denormalization
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- čas přidán 16. 01. 2021
- If you want to learn how to change De normalized dataset into 3rd normal form this video is for you
The video is part of the normalization series, Please watch these videos as well for better understanding on the entire concept.
The video is the 6th video in the video series of Normalization.
Here is the link to the 1st Video - normalization
www.youtube.com/watch?v=oDZUV...
Here is the link to the 2nd Video - 1st Normal form
www.youtube.com/watch?v=RyqhX...
The 2nd Normal focus on No Partial Dependency.
Here is the link to the 3rd Video - 2nd Normal form
• Second Normal Form in ...
The 3rd Normal focus on the transitive dependency.
www.youtube.com/watch?v=tJtZL...
#Keys #NormalizationSeries #TechCoach
Great work, most asked in interviews
Oh! Fantastic. I took three months to understand normalization but you just made me a genius within a second. Well done bro💪💪
I am glad I could help
Thank you so much! Getting ready for an exam, and you explained it very well :)
I am glad I could help :)
excellent explanation!
Great Video. For the 3NF part, I guess we have Teacher Email depending on the non-prime attribute Teacher, right? Given the Primary Key of that table is Course_Id. Right?
Thankss!
Awesome video😎😎👍👍
Great stuff...thank you for giving everyone an exercise...Learning is only fully realized by doing. It would be great if you could post a solution to the bonus problem. Also it would useful to extending this series to show how you could use this DB structure (e.g., Joins) to extract any data needed from it.
My Solution to "bonus" challenge:
1 - Student table (student_id, student_name)
2 - Teacher table (teacher_id, teacher_name)
3 - Course table (course_id, course_name)
Hey Buddy, thanks for the kind wordw Your solutions looks good to me , I will just put the column grade at the end and will recheck once more in the morning.
I plan to make an entire series on Oracle and sql pretty soon.
I thought of this same solution
Can we write in this way?
1 - Student table (student_id, student_name)
2- Teacher table (teacher_id, teacher_name, email)
3 - Course table (course_id, course_name)
4 - Students_Courses join Table (student_id, course_id, grade)
5 - Teacher_Course(course_id, teacher_id)
@@TechCoach i also noticed it’s common that 1nf - 2 tables, 2nf - 3, 3nf - 4 tables usually, like it gets added one by one, is it true?
Very nice explanation
Nice video, enjoyed the tennis references too
I am glad I could help :)
Here in converting the table in 3NF how could we know that we have to add an attribute of "Teacher-id".
gookd work
great explanation and graphics for teaching! 👍
Thanks buddy, please consider subscribing to my other channel as well it will really help me :)
czcams.com/video/6G1xGi-D5ow/video.html
Yes😊😊
You are a real one
I am glad I could help
sir plz make a video on tips to solve normalization 1nf , 2nf and 3nf . if u do , i will be grateful .
Sir in the video you said that student id and course id are primary keys but a primary key doesn't allow any duplicates in the column.how is it possible sir ?
I think that is why we are combining the course id and student id as compsoite key to make them unique
Great job 👍♥️
I am glad I could help
Finally understood😊
I am glad I could help :)
Nice Video Keep It Up
Thanks a lot
Well explained. thankyou
I am glad I could help
what is the reason behind the grade relying on student_ID and Course_ID ?
Sir can you answer my simple question? If a table has no compound key and is in 1FN then automatically it is in 2FN?
Definitely,true. And if the atomicity of values have been considered... It automatically in 2NF .
I have confusion in 3rd NF. I mean Teacher name is dependendent on Course ID, so even teacher name ks not given, we can still say that teacher Email is dependent on Course ID. Because teacher A is teaching code with ID 10
I think it’s not dependent because if the teacher gets changed, course id will still be there. Email is only dependent on Teacher name because if name is changed, it’ll be changed too. Idk that’s how i get it
table 1 ( student ) - student id, student name
table 2 ( course ) - course id, course name
table 3 ( teacher ) - teacher id, course id, teacher name, teacher email
table 4 ( student course table) - student_course id, student id, course id, grade
explain urself how
Wonderful bro! course name ,teacher id 5th mapping table will be added if we have two teachers for same course.
Thanks Sandeep for the kind words :)
Please consider subscribing to my other channel as well. It will really help me.
czcams.com/video/6G1xGi-D5ow/video.html
the first video is no longer available
This video made my day, Sir. I'm just revising the normalization chapter. You made my concept Base much stronger. Thank you.
@pranav I am glad I could help.
I have 3 more videos on normalisation you can look at them as well :)
we can use the email address as a primary key right? it's unique.
You are Rocking Vivek
@Ramesh, Thanks for the kind words.
Please consider subscribing to my other channel as well.
czcams.com/video/6G1xGi-D5ow/video.html
Last mai teacher id kahn sy aya koi bta skta h
Hi, can I know precisely what way to determine the composite primary key?
It means 2 keys are combining to form a primary key
In the above example studentID and CourseID together were the composite primary key of the original table
whatever two attributes make sense together, think of them as one, in this case if u take student id and course id and think of them as one (1,10) it kinda forms a singular key u can use to determine every other attribute
Why you added id colum with teacher table by your own in 3rd nf?
You can’t?
I think it is to accommodate the 1NF where each record should have a unique identifier.
@@rainremindsmetoyou7436 i don't think so
You said the given table is in 1NF, 1NF states that there is no multivalued attribute in the table, teacher email is multivalued attribute, then how it is in 1NF. Please explain?
Look every cell that no any multi value
For example : car, bus for single cell its called multi value
table 1 ( student ) - student_id, student name
table 2 ( course ) - course id, course name, teacher_id
table 3 ( teacher ) - teacher id, teacher name, teacher email
table 4 ( student _course) - student_ id, course_id, grade
Table 5 (Course_teacher) - course_id, teacher_id
Wrong. You wont be able to map the teachers, course to the student
Course Name; teacher;
Correct?
😊
Table 1) Student_ID,Student_Name
Table 2) Course_id,Course_Name
Table 3) Student_ID,Teacher,Teacher email,Grade
Table 4) Student_Id,Teacher ( For lossless decomposition)
Table 1 : student id, student name
2 : course I'd, course name
3 : teacher id, teacher name, email address
4 : student id, course Id, teacher id, Grade
this is my solotion
On spot🤗🥱
but email address is dependent on teacher name. This would be a non-key decency, violating 3NF.
Can we write in this way?
1 - Student table (student_id, student_name)
2- Teacher table (teacher_id, teacher_name, email)
3- Course table (course_id, course_name)
4 - Students_Courses join Table (student_id, course_id, grade) 5- Teacher_Course(course_id, teacher_id)
Didnt understand anything
Using complex words
If we could understand complex words we could have read our book
My apology. There are 3 other videos in this series . You should start with them . This is the 4th video
@@TechCoach bhai doesn't matter now
Exam over
I am at fault i should have paid attention in class.
1.student_id,student_name
2.course_id,course_name
3.teacher_id,teacher_name,teacher_email
4.student_id,course_id,teacher_id,grade
5.course_id,teacher_id.
please let me know if my ans is wrong.thanks.
5.course_id,teacher_id (Table) doesn't need Right?
@@gangardarwagle8938 I think you need this to link the course and teacher table? I'm not sure tho
Last mai teacher id kahn sy aya koi bta skta h