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How to write DataFrame to postgres table?
... the table
conn = engine.raw_connection()
cur = conn.cursor()
output = io.StringIO()
df.to_csv(output, sep='\t', header=False, index=False)
output.seek(0)
contents = output.getvalue()
cur.copy_from(output, 'table_name', null="") # null values become ''
conn.commit()
...
Declaration/definition of variables locations in ObjectiveC?
...In ObjC, they should only be used to declare constants, and generally only string constants. For instance:
extern NSString * const MYSomethingHappenedNotification;
You would then in your .m file declare the actual constant:
NSString * const MYSomethingHappenedNotification = @"MYSomethingHappened...
Prevent “overscrolling” of web page
...oll its content within. This works in Safari and in Chrome.
Edit
Why the extra <div>-element as a wrapper could be useful: Florian Feldhaus' solution uses slightly less code and works fine too. However, it can have a little quirk, when it comes to content that exceeds the viewport width. In ...
What is a “bundle” in an Android application
... can get the passed values by doing:
Bundle extras = intent.getExtras();
String tmp = extras.getString("myKey");
You can find more info at:
android-using-bundle-for-sharing-variables and
Passing-Bundles-Around-Activities
...
How do I adb pull ALL files of a folder present in SD Card
...ices to make sure your readable, type adb pull sdcard/ sdcard_(the date or extra) <---this file needs to be made in adb directory beforehand. PROFIT!
In other versions type adb pull mnt/sdcard/ sdcard_(the date or extra)
Remember to make file or your either gonna have a mess or it wont work.
...
How can I get file extensions with JavaScript?
...not a path, for practical reasons, I think it should be return filename.substring(0,1) === '.' ? '' : filename.split('.').slice(1).pop() || ''; This takes care of .file (Unix hidden, I believe) kind of files too. That is if you want to keep it as a one-liner, which is a bit messy to my taste.
...
What's wrong with nullable columns in composite primary keys?
...s version the "ext" part of the tuple is NOT NULL but defaults to an empty string -- which is semantically (and practically) different from a NULL. A NULL is an unknown, whereas an empty string is a deliberate record of "something not being present". In other words, "empty" and "null" are different ...
android asynctask sending callbacks to ui [duplicate]
...tput) {
Log.d("Response From Asynchronous task:", (String) output);
mbtnPress.setText((String) output);
}
});
asyncTask.execute(new Object[] { "Youe request to aynchronous task class is givi...
Install Application programmatically on Android
...<application
android:allowBackup="true"
android:label="@string/app_name">
<provider
android:name="android.support.v4.content.FileProvider"
android:authorities="${applicationId}.authorityStr"
android:exported="false"
and...
What is the fastest way to check if a class has a function defined?
...
The responses herein check if a string is the name of an attribute of the object. An extra step (using callable) is needed to check if the attribute is a method.
So it boils down to: what is the fastest way to check if an object obj has an attribute attrib...