Can anyone help me with this SQL task?
(1 votes)
Loading...Similar Posts
Which programming language for beginners?
ByRalf9619
I already asked a question yesterday, and I received a lot of great answers, but also some that left me a bit confused. I've been trying to teach myself Python for a while now, but I'm having a hard time creating something of my own and I get a little lost whenever I have to…
Which AI is suitable for chatting?
I mean for role-playing games where the AI can store the knowledge. It should ideally be free
Can you create a movie trailer from scratch using artificial intelligence?
I would like to have a movie trailer created with a text description for private use. Is this permitted and possible?
The name 'php' was not recognized as the name of a cmdlet, function, script file, or executable program."?
The name 'php' was not recognized as the name of a cmdlet, function, script file, or executable program." My terminal then displays this: php : Die Benennung "php" wurde nicht als Name eines Cmdlet, einer Funktion, einer Skriptdatei oder eines ausführbaren Programms erkannt. Überprüfen Sie die Schreibweise des Namens, oder ob der Pfad korrekt ist…
Website not findable via keywords on Google?
Hi guys, I created a website myself using WordPress. Until two weeks ago, it was perfectly discoverable using certain keywords when entering them into the Google search engine. My site was listed fourth on the first page. This worked perfectly for two years. Now, suddenly, my site is no longer discoverable at all. Unless you…
Search functionality on my website?
Hello, I'd like to draw on your knowledge again. I have a list of various documents on my website. Now I want to implement a search function for it. How should I go about this? Should the search function run purely in the frontend (using JavaScript) or should I run the search via the server…
If it were SQL, it would be easy, but this is some wild mathematical formulation of relationships I’ve never seen in 15 years as a database admin. However, one can see it roughly as a series of primary key-refuse-key relationships, even if one cannot apply this to databases.
But to make it short: You can imagine the letters as columns in a table and the tuples are the values. The values from the columns that are left of the arrow clearly determine the value of the columns on the right side from the arrow. As I understood, you’re supposed to find out now that Tupel is no longer given the clarity.
I made a table so you can see what I mean:
In the yellow marked cells, there is a deviation where a key refers to different values. This means that in all values, except the tuple b) the relation is violated (at least if I have understood it correctly)
thank you for your illustration, but I still don’t understand why the relation should be hurt
Because the values per key must always be clear. Once the table shows that the key 3 has the value 5, you cannot add a tuple where the key 3 suddenly has the value 4.
As I said, this is only very remotely applicable to SQL or to databases, but in databases one always tries to have as little redundancy as possible. Thus, for example, a customer should always be exactly under a customer number in the database, so that name or address changes are immediately applied correctly at all places.