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Entity Attribute Value Database vs. strict Relational Model Ecommerce
... @Zim, that sounds pretty much like option 3. Each row has 1-n extra "generic" columns, and the data stored in them is interpreted at the application level. You get the performance benefit of having all the data for one record in one place. The metadata about those columns needs to be st...
Generate JSON string from NSDictionary in iOS
I have a dictionary I need to generate a JSON string by using dictionary . Is it possible to convert it? Can you guys please help on this?
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How do you round to 1 decimal place in Javascript?
...nded.toFixed(1)
// fixed is always to 1 d.p.
// NOTE: .toFixed() returns a string!
// To convert back to number format
parseFloat(number.toFixed(2))
// 12.34
// but that will not retain any trailing zeros
// So, just make sure it is the last step before output,
// and use a number format during ca...
Contains method for a slice
...iom. Since you aren't interested in the value, you might also create a map[string]struct{} for example. Using an empty struct{} here has the advantage that it doesn't require any additional space and Go's internal map type is optimized for that kind of values. Therefore, map[string] struct{} is a po...
Is there a good way to attach JavaScript objects to HTML elements?
...gly to define this method jquery stores keys into a global dictionary in a string attribute on each element. The name of this string attribute is randomly generated when jquery is first loaded. (Suggesting that there isn't a good way to do there isn't a nicer way to do this only using the DOM)
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DateTime2 vs DateTime in SQL Server
...nts doesn't support date, time, or datetime2 and force you to convert to a string literal. If you're concerned more about compatability than precision, use datetime
– FistOfFury
Jun 25 '14 at 20:49
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Passing variable arguments to another function that accepts a variable argument list
...s is for general debugprinting only so I did this:
//Helper function
std::string osprintf(const char *fmt, ...)
{
va_list args;
char buf[1000];
va_start(args, fmt);
vsnprintf(buf, sizeof(buf), fmt, args );
va_end(args);
return buf;
}
which I then can use like this
Point2d...
Sorting a vector of custom objects
...
A simple example using std::sort
struct MyStruct
{
int key;
std::string stringValue;
MyStruct(int k, const std::string& s) : key(k), stringValue(s) {}
};
struct less_than_key
{
inline bool operator() (const MyStruct& struct1, const MyStruct& struct2)
{
ret...
Pandas - How to flatten a hierarchical index in columns
...ant to combine/join your MultiIndex into one Index (assuming you have just string entries in your columns) you could:
df.columns = [' '.join(col).strip() for col in df.columns.values]
Note: we must strip the whitespace for when there is no second index.
In [11]: [' '.join(col).strip() for col in...
Confused about __str__ on list in Python [duplicate]
...round, I understand that __str__ is something like a Python version of toString (while I do realize that Python is the older language).
...