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Error 1022 - Can't write; duplicate key in table
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The most likely you already have a constraint with the name iduser or idcategory in your database. Just rename the constraints if so.
Constraints must be unique for the entire database, not just for the specific table you are creating/altering.
To find out where the constraints are ...
Physical vs. logical / soft delete of database record?
...users username for new records. Working around this you could tack on a GUID to the deleted username column, but it's a very hacky workaround that I wouldn't recommend. Probably in that circumstance it would be better to just have a rule that once a username is used, it can never be replaced.)
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Sticky sidebar: stick to bottom when scrolling down, top when scrolling up
I have been looking for some time now for a solution to my sticky sidebar problem. I have a specific idea of how I would like it to act; effectively, I would like it to stick to the bottom as you scroll down, and then as soon as you scroll back up I would like it to stick to the top, in a fluid moti...
Is it possible to specify condition in Count()?
...y old, but I like the NULLIF trick for such scenarios, and I found no downsides so far. Just see my copy&pasteable example, which is not very practical though, but demonstrates how to use it.
NULLIF might give you a small negative impact on performance, but I guess it should still be faster tha...
What is the difference between up-casting and down-casting with respect to class variable
...ing: When we want to cast a Sub class to Super class, we use Upcasting(or widening). It happens automatically, no need to do anything explicitly.
Downcasting : When we want to cast a Super class to Sub class, we use
Downcasting(or narrowing), and Downcasting is not directly possible in Java, expl...
What are the pros and cons of both Jade and EJS for Node.js templating? [closed]
...ich make the code very confusing (at least for me)
a(href='/user/' + user.id)= user.name
Jade is also not designer-friendly. My designer friends often give me HTML and CSS (They switched to LESS recently but still want to use HTML), and for that reason if I use Jade I need to convert HTML to Jade...
Check if a div exists with jquery [duplicate]
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Unless in code above they got something like $('#DivID') = null; Lol)
– ZurabWeb
Nov 6 '13 at 21:14
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PHP Remove elements from associative array
...etimes an application architecture doesn't want you to mess with the array id, or makes it inconvenient. For instance, I use CakePHP quite a lot, and a database query returns the primary key as a value in each record, very similar to the above.
Assuming the array is not stupidly large, I would use...
Using the scrollwheel in GNU screen
...(I'm using Ubuntu's GNOME terminal). I fixed it by going to Edit -> Profile Preferences -> Scrolling, and unchecking "Use keystrokes to scroll on alternate screen". Note that I still needed to use Pistos's fix.
– Michael Krebs
Mar 11 '11 at 2:19
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How can I use a local image as the base image with a dockerfile?
... image called ubuntu different from the official one, your image will override it.
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