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Code First: Independent associations vs. Foreign key associations?
...ve a mental debate with myself every time I start working on a new project and I am designing my POCOs. I have seen many tutorials/code samples that seem to favor foreign key associations :
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Which is more efficient: Multiple MySQL tables or one large table?
...inally it was set up in various tables meaning data is linked with UserIds and outputting via sometimes complicated calls to display and manipulate the data as required. Setting up a new system, it almost makes sense to combine all of these tables into one big table of related content.
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Why I can't change directories using “cd”?
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Shell scripts are run inside a subshell, and each subshell has its own concept of what the current directory is. The cd succeeds, but as soon as the subshell exits, you're back in the interactive shell and nothing ever changed there.
One way to get around this is t...
Avoid trailing zeroes in printf()
...ll remove all but the first N decimals, then strip off the trailing zeros (and decimal point if they were all zeros).
char str[50];
sprintf (str,"%.20g",num); // Make the number.
morphNumericString (str, 3);
: :
void morphNumericString (char *s, int n) {
char *p;
int count;
p = str...
Extending from two classes
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You can only Extend a single class. And implement Interfaces from many sources.
Extending multiple classes is not available. The only solution I can think of is not inheriting either class but instead having an internal variable of each class and doing more o...
“git pull” or “git merge” between master and development branches
I have my master branch and a develop branch for working on a few changes. I need to merge changes from master into develop , but will eventually merge everything from develop into master . I have two different workflows in mind:
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Window.open and pass parameters by post method
...rect, with encoding of values in the HTML code), just open an empty window and post a form to it.
Example:
<form id="TheForm" method="post" action="test.asp" target="TheWindow">
<input type="hidden" name="something" value="something" />
<input type="hidden" name="more" value="someth...
How to get the input from the Tkinter Text Widget?
...) The -1c deletes 1 character, while -2c would mean delete two characters, and so on.
def retrieve_input():
input = self.myText_Box.get("1.0",'end-1c')
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What is the difference between “INNER JOIN” and “OUTER JOIN”?
Also how do LEFT JOIN , RIGHT JOIN and FULL JOIN fit in?
27 Answers
27
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MySQL, better to insert NULL or empty string?
...a lot of different fields. Some of the fields are optional while some are mandatory. In my DB I have a table which holds all these values, is it better practice to insert a NULL value or an empty string into the DB columns where the user didn't put any data?
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