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Check if null Boolean is true results in exception
...r null as any other object.
In your particular case, your Boolean is null and the if statement triggers an implicit conversion to boolean that produces the NullPointerException. You may need instead:
if(bool != null && bool) { ... }
...
OwinStartup not firing
I had the OwinStartup configuration code working perfectly and then it stopped working. Unfortunately I'm not sure exactly what I did to get it to stop working and am having a really hard time figuring it out.
...
git mv and only change case of directory
...h out the -A will not take care of the remove side of the mv as Git understands it. Warning! Ensure that no other changes or untracked files are around when you do this or they will get committed as part of this change! git stash -u first, do this and then git stash pop after. Continuing: To get aro...
How to find patterns across multiple lines using grep?
I want to find files that have "abc" AND "efg" in that order, and those two strings are on different lines in that file. Eg: a file with content:
...
SQLAlchemy - Getting a list of tables
...n you can use table reflection. SQLAlchemy will then inspect the database and update the metadata with all of the missing tables.
>>> metadata.reflect(engine)
For Postgres, if you have multiple schemas, you'll need to loop thru all the schemas in the engine:
from sqlalchemy import insp...
how to convert milliseconds to date format in android?
...t(dateFormat);
// Create a calendar object that will convert the date and time value in milliseconds to date.
Calendar calendar = Calendar.getInstance();
calendar.setTimeInMillis(milliSeconds);
return formatter.format(calendar.getTime());
}
}
I hope this help...
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Mime type for WOFF fonts?
...omment on Jun 22, 2017:
As of February 2017, RFC8081 is the proposed standard. It defines a top-level media type for fonts, therefore the standard media type for WOFF and WOFF2 are as follows:
font/woff
font/woff2
In January 2011 it was announced that in the meantime Chromium will ...
Dealing with multiple Python versions and PIP?
...This is the recommendation because it works across all versions of Python, and in all forms of virtualenv. For example:
# The system default python:
$ python -m pip install fish
# A virtualenv's python:
$ .env/bin/python -m pip install fish
# A specific version of python:
$ python-3.6 -m pip inst...
What's the fastest way to do a bulk insert into Postgres?
...
PostgreSQL has a guide on how to best populate a database initially, and they suggest using the COPY command for bulk loading rows. The guide has some other good tips on how to speed up the process, like removing indexes and foreign keys before loading the data (and adding them back afterward...
Unlimited Bash History [closed]
...want my .bash_history file to be unlimited. e.g. So I can always go back and see how I built/configured something, or what that nifty command was, or how some command broke something weeks ago. How do I change this setting?
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