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Can someone please answer this: (1 Viewer)
- Thread starter BowDown2
- Start date
ajdlinux
Mod: ANU, ATAR/HSC Marks
Well, one-to-many means that one record in one table is linked to many records in another table. Each customer can make many transactions, but each transaction is only linked with one customer.
Many-to-one means that there are several records linked to one record. For any one video in the store, it can be borrowed in many different transactions. However, each transaction only borrows one video. Also, there can be multiple copies of a movie, but each video is only one movie.
Many-to-one means that there are several records linked to one record. For any one video in the store, it can be borrowed in many different transactions. However, each transaction only borrows one video. Also, there can be multiple copies of a movie, but each video is only one movie.
dalillebpwinces
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OMGGGG WOOooHOooo
i suk at ipt and i got dis one! !!!!!!
lol i cant believe it !!! lisn you hav to think of it one to many is like.......theres onli 1 video but can be borrowd many times...think of it like that the video may have one id but in another table itll b there more than once coz its been burrowd more than once ,,,,one to many.... lol if u don get it then sit and stare at the question a bit bettr coz i got it in about 10 seconds it reali isnt a hard question...
:worried: i hate IPT!
and i made a big mistake gettin into it! im good at it n everythin but eww! i neva wanna have to think about routers and schema's in the future!
good luk pplz
peace...
Mona.
i suk at ipt and i got dis one! !!!!!!
lol i cant believe it !!! lisn you hav to think of it one to many is like.......theres onli 1 video but can be borrowd many times...think of it like that the video may have one id but in another table itll b there more than once coz its been burrowd more than once ,,,,one to many.... lol if u don get it then sit and stare at the question a bit bettr coz i got it in about 10 seconds it reali isnt a hard question...
:worried: i hate IPT!
and i made a big mistake gettin into it! im good at it n everythin but eww! i neva wanna have to think about routers and schema's in the future!
good luk pplz
peace...
Mona.
Starcraftmazter
Member
I lol'd.
First Column
Customers table contains customers, only one record per customer.
Transactions table contains transactions. There is no limit on transactions - think in the shop, you can borrow lots of things, many times. But there is only one of you.
So it's a one-to-many relationship, since there is only one of you, but there is no specified limit to how many transactions (ie. borrowings as as simplification) you can make.
Second Column
Ok, so you have videos and transactions. Now you have individual videos, which will be borrowed over and over by different or the same customers. The point is, any one video will be involved in many transactions over time.
This is why there are many transactions for every one video.
Hence a many-to-one relationship between transactions and videos.
Third Column
Video shops always buy many copies of one movie, so they don't run out. For example, when 300 comes in, and there are 3000 people whom want to rent it
Anyway, 300 is just one (awesome) movie, but the store might have like 50 copies of it. So there are 50 videos and 1 movie.
Hence a many to one relationship between videos and movies.
Does that make sense? Because if it does, Me > Ajd, officially
First Column
Customers table contains customers, only one record per customer.
Transactions table contains transactions. There is no limit on transactions - think in the shop, you can borrow lots of things, many times. But there is only one of you.
So it's a one-to-many relationship, since there is only one of you, but there is no specified limit to how many transactions (ie. borrowings as as simplification) you can make.
Second Column
Ok, so you have videos and transactions. Now you have individual videos, which will be borrowed over and over by different or the same customers. The point is, any one video will be involved in many transactions over time.
This is why there are many transactions for every one video.
Hence a many-to-one relationship between transactions and videos.
Third Column
Video shops always buy many copies of one movie, so they don't run out. For example, when 300 comes in, and there are 3000 people whom want to rent it
Anyway, 300 is just one (awesome) movie, but the store might have like 50 copies of it. So there are 50 videos and 1 movie.
Hence a many to one relationship between videos and movies.
Does that make sense? Because if it does, Me > Ajd, officially
you basically answered the question then. the relationship has to be connected to the same table. hence why u got it wrong. in terms of the many to one or one to many:
1. One-to-Many: there are many Movie_IDs because several videos cannot have the same id otherwise they can not be identified. however its only one as the videos are all of the same movie (see previous posts) therefore 1 movie NAME to many move ID.
2. Many-to-one: there are a lot of members of the video shop but a person can only have one member account therefore a lot of member IDs but a single ID can only be linked to one Name.
hope i helped a bit.
i didn't understand this stuff last yr but now i do
1. One-to-Many: there are many Movie_IDs because several videos cannot have the same id otherwise they can not be identified. however its only one as the videos are all of the same movie (see previous posts) therefore 1 movie NAME to many move ID.
2. Many-to-one: there are a lot of members of the video shop but a person can only have one member account therefore a lot of member IDs but a single ID can only be linked to one Name.
hope i helped a bit.
i didn't understand this stuff last yr but now i do
