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Is it a good idea to index datetime field in mysql?
...n/5.0/en/mysql-indexes.html
This makes your datetime column an excellent candidate for an index if you are going to be using it in conditions frequently in queries. If your only condition is BETWEEN NOW() AND DATE_ADD(NOW(), INTERVAL 30 DAY) and you have no other index in the condition, MySQL will...
Create a temporary table in a SELECT statement without a separate CREATE TABLE
...only) table from a select statement without using a create table statement and specifying each column type? I know derived tables are capable of this, but those are super-temporary (statement-only) and I want to re-use.
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Find all storage devices attached to a Linux machine [closed]
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/proc/partitions will list all the block devices and partitions that the system recognizes. You can then try using file -s <device> to determine what kind of filesystem is present on the partition, if any.
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How to output messages to the Eclipse console when developing for Android
...int messages (like a flag) to the Eclipse console (or log) when developing and debugging an Android app
5 Answers
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bash assign default value
...=${LONG_VARIABLE_NAME:-hello} , but now bash also tries to execute 'hello' and that gives a command not found. Any way to avoid that? Or will I have to stick to the latter? Can someone give an example where the assign default is actually useful?
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The thread has exited with code 0 (0x0) with no unhandled exception
... message. You can switch that off by right clicking into the output window and uncheck Thread Exit Messages.
http://msdn.microsoft.com/en-us/library/bs4c1wda.aspx
In addition to program out from your application, the Output window
can display the information about:
Modules the debugg...
What do (lambda) function closures capture?
Recently I started playing around with Python and I came around something peculiar in the way closures work. Consider the following code:
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Assign pandas dataframe column dtypes
...you have to use the explicit conversions:
pd.to_datetime, pd.to_timedelta and pd.to_numeric
(As mentioned below, no more "magic", convert_objects has been deprecated in 0.17)
df = pd.DataFrame({'x': {0: 'a', 1: 'b'}, 'y': {0: '1', 1: '2'}, 'z': {0: '2018-05-01', 1: '2018-05-02'}})
df.dtypes
x ...
jQuery UI accordion that keeps multiple sections open?
...doesn't allow more than
one content panel to be open at the
same time, and it takes a lot of
effort to do that. If you are looking
for a widget that allows more than one
content panel to be open, don't use
this. Usually it can be written with a
few lines of jQuery instead, something
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How to convert byte array to Bitmap
...ant to store image in SQLite DataBase .
I tried to store it using BLOB and String , in both cases it store the
image and can retrieve it but when i convert it to Bitmap using
BitmapFactory.decodeByteArray(...) it return null.
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