SQL keys, MUL vs PRI vs UNI?

What is the difference between MUL, PRI and UNI in MySQL? I'm working on a MySQL query, using the command: desc my...

Python - converting textfile contents into dictionary values/keys easily?

Let's say I have a text file with the following: line = "this is line 1" line2 = "this is the second line" line3 = ...

What is key=lambda?

While using some built-in functions like sorted, sum... I noticed the usage of key=lambda What is lambda? How does ...

php - push array into array - key issue?

i am trying to push multiple arrays into 1 big array, resulting in a 2 lvl array. I got this set of arrays for exam...

How to update a value, given a key in a hashmap??

Suppose we have a HashMap<String, Integer> in Java. How do I update (increment) the integer-value of the stri...

How to get RSA key from -----BEGIN CERTIFICATE--— from.crt and .pem file??

I'm having .crt and .pem file with -----BEGIN CERTIFICATE----- MIIFSDCCBDCg.........................................

There are no primary or candidate keys in the referenced table that match the referencing column list in the foreign key?

In SQL Server , I got this error -> "There are no primary or candidate keys in the referenced table 'BookT...

SQL keys, MUL vs PRI vs UNI?

What is the difference between MUL, PRI and UNI in MySQL? I'm working on a MySQL query, using the command: desc my...

SQL keys, MUL vs PRI vs UNI?

What is the difference between MUL, PRI and UNI in MySQL? I'm working on a MySQL query, using the command: desc my...

BLOB/TEXT column 'bestilling' used in key specification without a key length?

I am trying to make a order system, but I am stuck right now. In the mysql tabel right now, I am using varchar(255) ...

SSH Key: “Permissions 0644 for 'id_rsa.pub' are too open.” on mac?

I generate a ssh key pair on my mac and add the public key to my ubuntu server(in fact, it is a virtual machine on m...

ssh-keygen' is not recognized as an internal or external command?

I am trying to add ssh keys for usage on github but on my xp on command prompt ssh-keygen does not work. It gives me...

Which characters are valid/invalid in a JSON key name??

Are there any forbidden characters in key names, for JavaScript objects or JSON strings? Or characters that need to ...