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How do I concatenate two arrays in C#?
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How is that more efficient than x.Concat(y)? It works and all, I'm just wondering if there is something that makes it better?
– Mike Two
Oct 10 '09 at 7:07
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SQL: capitalize first letter only [duplicate]
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select replace(wm_concat(new),',','-') exp_res from (select distinct initcap(substr(name,decode(level,1,1,instr(name,'-',1,level-1)+1),decode(level,(length(name)-length(replace(name,'-','')))+1,9999,instr(name,'-',1,level)-1-decode(level,1,0,i...
How do I truncate a .NET string?
...rmance testing is fun: (using linqpad extension methods)
var val = string.Concat(Enumerable.Range(0, 50).Select(i => i % 10));
foreach(var limit in new[] { 10, 25, 44, 64 })
new Perf<string> {
{ "newstring" + limit, n => new string(val.Take(limit).ToArray()) },
{ "c...
Update MongoDB field using value of another field
...lection.<update method>(
{},
[
{"$set": {"name": { "$concat": ["$firstName", " ", "$lastName"]}}}
]
)
MongoDB 3.4+
In 3.4+ you can use $addFields and the $out aggregation pipeline operators.
db.collection.aggregate(
[
{ "$addFields": {
"name": {...
Select by partial string from a pandas DataFrame
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Performance wise, regex search is slower than substring search:
df2 = pd.concat([df1] * 1000, ignore_index=True)
%timeit df2[df2['col'].str.contains('foo')]
%timeit df2[df2['col'].str.contains('foo', regex=False)]
6.31 ms ± 126 µs per loop (mean ± std. dev. of 7 runs, 100 loops each)
2.8 ms ...
Why doesn't nodelist have forEach?
...to mean that the instance was an Array in combination with Array.prototype.concat.
There was a bug in Google's Closure Library which caused almost all Google's apps to fail due to this. The library was updated as soon as this was found but there might still be code out there that makes the same inco...
Split value from one field to two
...It's almost invariably a lot faster to join columns together with a simple concatenation (when you need the full name) than it is to split them apart with a character search.
If, for some reason you cannot split the field, at least put in the extra columns and use an insert/update trigger to popula...
Convert NSArray to NSString in Objective-C
...obj in array)
{
[result appendString:[obj description]];
}
NSLog(@"The concatenated string is %@", result);
Another approach would be to do something based on each item's class:
NSMutableString * result = [[NSMutableString alloc] init];
for (NSObject * obj in array)
{
if ([obj isKindOfCla...
How can I append a string to an existing field in MySQL?
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You need to use the CONCAT() function in MySQL for string concatenation:
UPDATE categories SET code = CONCAT(code, '_standard') WHERE id = 1;
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How to extend an existing JavaScript array with another array, without creating a new array
...ed for "JavaScript array extend" and got here, you can very well use Array.concat.
var a = [1, 2, 3];
a = a.concat([5, 4, 3]);
Concat will return a copy the new array, as thread starter didn't want. But you might not care (certainly for most kind of uses this will be fine).
There's also some n...