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How to store arrays in MySQL?
I have two tables in MySQL. Table Person has the following columns:
7 Answers
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How to create an infinite loop in Windows batch file?
... I want in a batch file. I want to be able to re-run "Do Stuff" whenever I press any key to go past the "Pause".
6 Answer...
Difference between the Facade, Proxy, Adapter and Decorator design patterns? [closed]
What is the difference between the Facade, Proxy, Adapter, and Decorator design patterns?
2 Answers
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Text border using css (border around text)
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Use multiple text shadows:
text-shadow: 2px 0 0 #fff, -2px 0 0 #fff, 0 2px 0 #fff, 0 -2px 0 #fff, 1px 1px #fff, -1px -1px 0 #fff, 1px -1px 0 #fff, -1px 1px 0 #fff;
body {
font-family: sans-serif;
background: #222;
c...
How should one use std::optional?
I'm reading the documentation of std::experimental::optional and I have a good idea about what it does, but I don't understand when I should use it or how I should use it. The site doesn't contain any examples as of yet which leaves it harder for me to grasp the true concept of this object. When...
SQL statement to get column type
Is there a SQL statement that can return the type of a column in a table?
22 Answers
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Surrogate vs. natural/business keys [closed]
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Both. Have your cake and eat it.
Remember there is nothing special about a primary key, except that it is labelled as such. It is nothing more than a NOT NULL UNIQUE constraint, and a table can have more than one.
If you use a surrogate key, you still want a business key to ensure u...
How do I drop a function if it already exists?
I know this must be simple, but how do I preface the creation of a function with a check to see if it already exists? If it exists, I want to drop and re-create it.
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Selecting only numeric columns from a data frame
Suppose, you have a data.frame like this:
11 Answers
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Remove everything after a certain character
... to remove everything after a certain character or just choose everything up to that character? I'm getting the value from an href and up to the "?", and it's always going to be a different amount of characters.
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