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mysql Foreign key constraint is incorrectly formed error
I have two tables, table1 is the parent table with a column ID and table2 with a column IDFromTable1 (not the actual name) when I put a FK on IDFromTable1 to ID in table1 I get the error Foreign key constraint is incorrectly formed error . I would like to delete table 2 record if tab...
How to make a element expand or contract to its parent container?
The goal is to have the <svg> element expand to the size of its parent container, in this case a <div> , no matter how big or small that container may be.
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Xcode : failed to get the task for process
This is for an existing app that compiled and distributed multiple times. Since updating to Xcode 5 I have this error popping.
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Provide an image for WhatsApp link sharing
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2020 standards
It takes a few steps to get the perfect preview for WhatsApp, Twitter, Facebook and bookmark icons for pc's and mobile devices. If you like reading go to ogp.me - but make sure to read steps 1 - 6 in this answer to ge...
Difference between Node object and Element object?
I am totally confused between Node object and Element object.
document.getElementById() returns Element object while document.getElementsByClassName()
returns NodeList object(Collection of Elements or Nodes?)
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How do I perform the SQL Join equivalent in MongoDB?
...t array field>
}
}
Of course Mongo is not a relational database, and the devs are being careful to recommend specific use cases for $lookup, but at least as of 3.2 doing join is now possible with MongoDB.
share
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append multiple values for one key in a dictionary [duplicate]
I am new to python and I have a list of years and values for each year. What I want to do is check if the year already exists in a dictionary and if it does, append the value to that list of values for the specific key.
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What are the most common SQL anti-patterns? [closed]
...d (or are learning) that SQL is different. Eliciting the desired results, and doing so efficiently, involves a tedious process partly characterized by learning unfamiliar paradigms, and finding out that some of our most familiar programming patterns don't work here. What are the common antipattern...
What is the use of the ArraySegment class?
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ArraySegment<T> has become a lot more useful in .NET 4.5+ and .NET Core as it now implements:
IList<T>
ICollection<T>
IEnumerable<T>
IEnumerable
IReadOnlyList<T>
IReadOnlyCollection<T>
as opposed to the .NET 4 version which implemented no interfaces...
Regular cast vs. static_cast vs. dynamic_cast [duplicate]
I've been writing C and C++ code for almost twenty years, but there's one aspect of these languages that I've never really understood. I've obviously used regular casts i.e.
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