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How to create a MySQL hierarchical recursive query
...s, path IDs, or self-joins.
MySQL 8+
with recursive cte (id, name, parent_id) as (
select id,
name,
parent_id
from products
where parent_id = 19
union all
select p.id,
p.name,
p.parent_id
from products p
inn...
Capitalize or change case of an NSString in Objective-C
...ingString:lowercase];
}
- (NSString *)realSentenceCapitalizedString {
__block NSMutableString *mutableSelf = [NSMutableString stringWithString:self];
[self enumerateSubstringsInRange:NSMakeRange(0, [self length])
options:NSStringEnumerationBySentences
...
Which websocket library to use with Node.js? [closed]
...process.env.PORT || 5000;
var app = express();
app.use(express.static(__dirname+ "/../"));
app.get('/someGetRequest', function(req, res, next) {
console.log('receiving get request');
});
app.post('/somePostRequest', function(req, res, next) {
console.log('receiving pos...
How to specify data attributes in razor, e.g., data-externalid=“23151” on @this.Html.CheckBoxFor(…)
...el.MyBoolProperty,
new {
@class = "myCheckBox",
data_externalid = "23521"
}
)
The _ will automatically be converted to - in the resulting markup:
<input type="checkbox" name="MyModel.MyBoolProperty" data-externalid="23521" class="myCheckBox" />
And that's true f...
Precision String Format Specifier In Swift
...
a simple way is:
import Foundation // required for String(format: _, _)
print(String(format: "hex string: %X", 123456))
print(String(format: "a float number: %.5f", 1.0321))
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Unable to install gem - Failed to build gem native extension - cannot load such file — mkmf (LoadErr
...ing so i had to run open /Library/Developer/CommandLineTools/Packages/macOS_SDK_headers_for_macOS_10.14.pkg
That didnt work for me at first because the version of CommandLineTools i had installed did not have the "Packages" folder. So i uninstalled and reinstalled like this:
rm -rf /Library/Devel...
Remove rows with duplicate indices (Pandas DataFrame and TimeSeries)
...re readable.
Using the sample data provided:
>>> %timeit df3.reset_index().drop_duplicates(subset='index', keep='first').set_index('index')
1000 loops, best of 3: 1.54 ms per loop
>>> %timeit df3.groupby(df3.index).first()
1000 loops, best of 3: 580 µs per loop
>>> %tim...
Is MonoTouch now banned on the iPhone? [closed]
...PIs and built-in interpreter(s). http://adcdownload.apple.com/iphone/iphone_sdk_3.2__final/iphone_sdk_agreement.pdf
Even though that's the case (and was actually the case since 2.x, apple doesn't have any problem accepting applications that do exactly that. For example, ALL EA games use Lua script...
What is lexical scope?
...ipt our choices for scoping are:
as-is (no scope adjustment)
lexical var _this = this; function callback(){ console.log(_this); }
bound callback.bind(this)
It's worth noting, I think, that JavaScript doesn't really have dynamic scoping. .bind adjusts the this keyword, and that's close, but not t...
@try - catch block in Objective-C
...t length] - 1);
}
@finally {
NSLog(@"Finally condition");
}
Log:
[__NSCFConstantString characterAtIndex:]: Range or index out of bounds
Char at index 5 cannot be found
Max index is: 3
Finally condition
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