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SQL - many-to-many table primary key
...at the table sorted, just the index. And the index won't be stored sequentially, it'll be stored in an efficient manner to be able to be retrieved quickly.
In addition, the vast majority of database tables are read far more often than written. That makes anything you do on the select side far more ...
How to get HTTP response code for a URL in Java?
...od, I get an IOException ("Failed to authenticate with proxy") which is usually an http error 407. Is there a way where I can get a precision (the http error code) about the exception raised by the getRespondeCode() method? By the way, I know how to handle my error, and I just want to know how to di...
$(window).width() not the same as media query
...ve to support more browsers you can use Modernizr's mq method, it supports all browsers that understand media queries in CSS.
if (Modernizr.mq('(max-width: 767px)')) {
//...
} else {
//...
}
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Android on-screen keyboard auto popping up
One of my apps has an "opening screen" (basically a menu) that has an EditText followed by several Button s. The problem is that several of my users are reporting that when they open the app it's automatically popping up the on-screen keyboard without them even touching the EditText . As far as ...
Replacing Pandas or Numpy Nan with a None to use with MysqlDB
...s:
df1 = df.where(pd.notnull(df), None)
Note: this changes the dtype of all columns to object.
Example:
In [1]: df = pd.DataFrame([1, np.nan])
In [2]: df
Out[2]:
0
0 1
1 NaN
In [3]: df1 = df.where(pd.notnull(df), None)
In [4]: df1
Out[4]:
0
0 1
1 None
Note: what you ca...
Linq style “For Each” [duplicate]
...
Calling ToList followed by ForEach involves iterating through the original collection twice. I'd prefer a standard foreach loop any day: less typing, more readable and better performance: foreach (var x in someValues) list.Add...
What are Java command line options to set to allow JVM to be remotely debugged?
...ave this article bookmarked on setting this up for Java 5 and below.
Basically run it with:
-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=n,address=1044
For Java 5 and above, run it with:
-agentlib:jdwp=transport=dt_socket,server=y,suspend=y,address=1044
...
Getting rid of \n when using .readlines() [duplicate]
...string:
for i in contents:
alist.append(i.rstrip('\n'))
This leaves all other whitespace intact. If you don't care about whitespace at the start and end of your lines, then the big heavy hammer is called .strip().
However, since you are reading from a file and are pulling everything into mem...
Android draw a Horizontal line between views
...d of hardcoding it. I tried your suggestion, which I think would be technically better, but it didn't seem to work - I didn't get any dividers in my layouts. How should I use it? Thank you.
– nsandersen
Jul 4 '19 at 22:39
...
Parse v. TryParse
...l indicating whether it succeeded.
TryParse does not just try/catch internally - the whole point of it is that it is implemented without exceptions so that it is fast. In fact the way it is most likely implemented is that internally the Parse method will call TryParse and then throw an exception if...