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Storing money in a decimal column - what precision and scale?

...onverting a floating point number back to an integer in step 3, don't just cast it - use a math function to round it first. This will usually be round, though in special cases it could be floor or ceil. Know the difference and choose carefully. Store the type of a number alongside the value This m...
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How to compare two colors for similarity/difference

...t;/b> pctDiffRed = diffRed / 255; is going to give you 0 unless you cast to a float somewhere. <b>2</b> You'll need to multiply by 100 somewhere to get a percentage. – vaughandroid Jan 26 '12 at 12:34 ...
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Why exactly is eval evil?

...nic or other) pointers restartable exceptions self-modifying code ...and a cast of thousands. If you find yourself having to use any of these powerful, potentially dangerous tools ask yourself three times "why?" in a chain. For example: "Why do I have to use eval?" "Because of foo." "Why ...
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Checking for empty arrays: count vs empty

... Alternatively, you can cast the variable as a boolean (implicitly or explicitly): if( $value ) { // array is not empty } if( (bool) $value ) { // array is still not empty } This method does generate an E_NOTICE if the variable is not define...
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How to speed up insertion performance in PostgreSQL

...h statement using SQLSetConnectAttr(conn, SQL_ATTR_AUTOCOMMIT, reinterpret_cast<SQLPOINTER>(SQL_AUTOCOMMIT_OFF), 0); Once all rows have been inserted, commit the transaction using SQLEndTran(SQL_HANDLE_DBC, conn, SQL_COMMIT);. There is no need to explicitly open a transaction. Unfortunately,...
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returning a Void object

... If you want to return null as void you need to cast it in some cases: (Void) null – Patrick Favre Mar 29 '16 at 10:04 ...
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How do I check if a list is empty?

... Part 1 The "pythonic" way fails with NumPy arrays because NumPy tries to cast the array to an array of bools, and if x tries to evaluate all of those bools at once for some kind of aggregate truth value. But this doesn't make any sense, so you get a ValueError: >>> x = numpy.array([0,1]...
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What does 'const static' mean in C and C++?

...e you saying const declaration implies static there as well? As in, if you cast const away, and modify the value, all values will be modified? – Cookie Mar 26 '14 at 20:44 1 ...
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Random string generation with upper case letters and digits

... If you want to skip the string casting & hyphen replacing, you can just call my_uuid.get_hex() or uuid.uuid4().get_hex() and it will return a string generated from the uuid that does not have hyphens. – dshap Apr ...
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How to strip all non-alphabetic characters from string in SQL Server?

...nstead of NVARCHAR within his function otherwise, your system will need to cast the string values from VARCHAR to NVARCHAR before it can perform the function which is more expensive. Even with those changes your function still might be faster, but those are a few examples I can see where his functi...