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How do I get a raw, compiled SQL query from a SQLAlchemy expression?
I have a SQLAlchemy query object and want to get the text of the compiled SQL statement, with all its parameters bound (e.g. no %s or other variables waiting to be bound by the statement compiler or MySQLdb dialect engine, etc).
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What is the advantage to using bloom filters?
I am reading up on bloom filters and they just seem silly. Anything you can accomplish with a bloom filter, you could accomplish in less space, more efficiently, using a single hash function rather than multiple, or that's what it seems. Why would you use a bloom filter and how is it useful?
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Set value for particular cell in pandas DataFrame using index
I've created a Pandas DataFrame
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Will strlen be calculated multiple times if used in a loop condition?
...tion. If it might, then you'll need to either call strlen() each time, or handle it through more complicated logic.
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Detecting an undefined object property
...ined`");
}
To check if an object does not actually have such a property, and will therefore return undefined by default when you try and access it:
if(!o.hasOwnProperty('myProperty')) {
alert("myProperty does not exist");
}
To check if the value associated with an identifier is the special va...
Convert from MySQL datetime to another format with PHP
...$phpdate );
The line $phpdate = strtotime( $mysqldate ) accepts a string and performs a series of heuristics to turn that string into a unix timestamp.
The line $mysqldate = date( 'Y-m-d H:i:s', $phpdate ) uses that timestamp and PHP's date function to turn that timestamp back into MySQL's standa...
Who architected / designed C++'s IOStreams, and would it still be considered well-designed by today'
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Several ill-conceived ideas found their way into the standard: auto_ptr, vector<bool>, valarray and export, just to name a few. So I wouldn't take the presence of IOStreams necessarily as a sign of quality design.
IOStreams have a checkered history. They are actually a rew...
How can I split a string into segments of n characters?
As the title says, I've got a string and I want to split into segments of n characters.
12 Answers
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Web workers without a separate Javascript file?
... I can tell, web workers need to be written in a separate JavaScript file, and called like this:
25 Answers
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String concatenation: concat() vs “+” operator
Assuming String a and b:
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