Normalisation and ERD

แชร์
ฝัง
  • เผยแพร่เมื่อ 4 ต.ค. 2024
  • How to normalise and draw an Entity Relationship Diagram
    #normalisation
    #youtube
    #1NF
    #2NF
    #3NF
    #first normal form
    #databases

ความคิดเห็น • 43

  • @im0122
    @im0122 3 ปีที่แล้ว +6

    you havent posted in 3 years but you r still helping ,thank you

    • @learnwithnadia1455
      @learnwithnadia1455  3 ปีที่แล้ว +1

      One of my students opened the account for me as he really wanted me to.. but I have been slow in production ;--)

  • @shafiullahsyed4255
    @shafiullahsyed4255 5 ปีที่แล้ว +6

    wow what a sweet voice and thanks for the lecture

  • @IBRAHIM-vz1un
    @IBRAHIM-vz1un 3 ปีที่แล้ว +3

    Thank you very much Nadia! 👍🏼
    God bless you 🤲🏼 This is gonna help me in my final exam.
    You have a beautiful voice and accent, along with explaining things in an amazing way.

  • @husnimasha3324
    @husnimasha3324 6 ปีที่แล้ว +13

    Powerful lecture. I understood you more than I do to my lecturer
    Thanks alot

  • @sandarusampath7463
    @sandarusampath7463 ปีที่แล้ว

    Very helpful and clear explaination. Thank you🔥

  • @alvisceratortheultimate1660
    @alvisceratortheultimate1660 3 ปีที่แล้ว +1

    This is truly helpful, thank you.

  • @ubermensche60
    @ubermensche60 6 ปีที่แล้ว +2

    Now this was very helpful.....

  • @sumedhakarunarathna426
    @sumedhakarunarathna426 4 ปีที่แล้ว +1

    Thank you this was really useful...

  • @vihangamuthumal3981
    @vihangamuthumal3981 6 หลายเดือนก่อน

    its very helpful in 2024

  • @9252000lai
    @9252000lai 6 หลายเดือนก่อน

    can you explain why tour_id is the foreign key of customer?

  • @someoneleo230
    @someoneleo230 4 ปีที่แล้ว

    Very cute and informative.

  • @aimanmeer9005
    @aimanmeer9005 9 หลายเดือนก่อน

    Thanks alot teacher ❤

    • @learnwithnadia1455
      @learnwithnadia1455  8 หลายเดือนก่อน +1

      Nice to be address as a teacher again. I have not been teaching since 2021. I miss my students 😭. In fact it was a student that got me to create a TH-cam account and teach! But I have not done it regularly. It was just as extra lessons for my students.

    • @aimanmeer9005
      @aimanmeer9005 8 หลายเดือนก่อน

      @@learnwithnadia1455 ❤️🤍

  • @afzaalawan
    @afzaalawan 6 ปีที่แล้ว +3

    Excellent Nadia.. wiesh to be your student if you are in UK

    • @learnwithnadia1455
      @learnwithnadia1455  6 ปีที่แล้ว

      Thanks Afzaal, but I am in Australia.

    • @afzaalawan
      @afzaalawan 6 ปีที่แล้ว

      Too far. Any of here drop me a msg.

  • @levaitherapdragon
    @levaitherapdragon 6 หลายเดือนก่อน

    you just helped clear a course 🫶🏿🫵🏿

  • @MIqbalHossain
    @MIqbalHossain 6 ปีที่แล้ว +3

    2:49 ... why custId (001) have 2 entries? Customer ID is primary key, so there is a duplication.

    • @learnwithnadia1455
      @learnwithnadia1455  6 ปีที่แล้ว +4

      M Iqbal Hossain - that is unnormalised data where the same customer can be listed more than once. Later on when it is normalised it will only appear once.

  • @amruthakuruba166
    @amruthakuruba166 9 หลายเดือนก่อน +1

    there are two primary keys in a table custid and tourid how its possible

    • @learnwithnadia1455
      @learnwithnadia1455  9 หลายเดือนก่อน

      @amruthakuruba166 in some cases we need to combine two PKs from different tables to ensure a record is unique. This is called a composite key.

  • @TheRoyalRat778
    @TheRoyalRat778 4 ปีที่แล้ว

    Thank you!

  • @maramj8670
    @maramj8670 7 ปีที่แล้ว +1

    thank you so much, that was helpful!

    • @learnwithnadia1455
      @learnwithnadia1455  7 ปีที่แล้ว

      Glad to hear! You are welcome.

    • @maramj8670
      @maramj8670 7 ปีที่แล้ว +1

      We are studying a course which we have to create a system and we assigned to do a normalization, EDR and DFD for it, but the issue is that we studied database normalization way too back and we don't have our books and now we are confused about it, we remember just a little things. idk why i am telling you all this nonsense story but i just wanna know if we have to do 1NF, 2NF and 3NF also? or just one table would be enough? thank you so much for your time..

    • @learnwithnadia1455
      @learnwithnadia1455  7 ปีที่แล้ว

      If it is a course, I assume there are marks allocated for showing step by step normalisation. If not you can ensure all the requirements are met and reach 3NF at once and show only the final form.

  • @kseeroo
    @kseeroo 6 ปีที่แล้ว +1

    Wow Nadia, such a nice way to teach!!

    • @kseeroo
      @kseeroo 6 ปีที่แล้ว

      I hope you were the tutor, i got DB exam today about ERD Diagram and conversion. I should have contacted you earlier

  • @knowledgepoint2234
    @knowledgepoint2234 8 หลายเดือนก่อน +1

    I need for notes this lecture plz

    • @learnwithnadia1455
      @learnwithnadia1455  8 หลายเดือนก่อน

      It was done over 6 years ago, I will have to dig them up. Need your email to send to you.

  • @sulemanmasood1382
    @sulemanmasood1382 2 ปีที่แล้ว

    sir my db is in mysql using MYISAM.... No foreign keys implemented with some columns repeating in tables as well... i have approximatelly 40 tables and all containns approx 500 rows.... but two or 3 tables contains above one million rows....db is not normalized.....but it is still working fine...on LAN and on cloud as well ... what will be future of my db... can u help me...

  • @karansagar7870
    @karansagar7870 5 ปีที่แล้ว

    Are foreign keys shown in er diagram as attribute widout normalizing?

  • @hassankhattak3083
    @hassankhattak3083 2 ปีที่แล้ว +1

    Can I have these files in png or jpg form ASAP?

    • @learnwithnadia1455
      @learnwithnadia1455  8 หลายเดือนก่อน

      It was done 6 years ago, if I can find it I will. But how can I send it to you anyway.

  • @qasimateeq729
    @qasimateeq729 5 ปีที่แล้ว

    In 1st normal form u form 3 tables but in customer table "Cust_Id 001" is again repeated

    • @learnwithnadia1455
      @learnwithnadia1455  5 ปีที่แล้ว

      Qasim Ateeq 1NF can have that. Sorry I can see why you were confused. I should have shown the unnormalised form in another way. Repeating fields are not quite clear in my video- thanks for your query! I will do another video with another example!

  • @Pakhtoon_Afghan
    @Pakhtoon_Afghan 2 ปีที่แล้ว

    za za roka sha makh dy rok sha🤔