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How to change a nullable column to not nullable in a Rails migration?
I created a date column in a previous migration and set it to be nullable. Now I want to change it to be not nullable. How do I go about doing this assuming there are null rows in that database? I'm ok with setting those columns to Time.now if they're currently null.
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What to add for the update portion in ConcurrentDictionary AddOrUpdate
...f an update. I guess in your case (since you don't distinguish between add and update) this would be:
var sessionId = a.Session.SessionID.ToString();
userDic.AddOrUpdate(
authUser.UserId,
sessionId,
(key, oldValue) => sessionId);
I.e. the Func always returns the sessionId, so that both A...
How to extract text from a PDF? [closed]
Can anyone recommend a library/API for extracting the text and images from a PDF?
We need to be able to get at text that is contained in pre-known regions of the document, so the API will need to give us positional information of each element on the page.
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Duplicating a MySQL table, indices, and data
How do I copy or clone or duplicate the data, structure,
and indices of a MySQL table to a new one?
10 Answers
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Can Selenium interact with an existing browser session?
...nybody know if Selenium (WebDriver preferably) is able to communicate with and act through a browser that is already running before launching a Selenium Client?
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Is it possible to break a long line to multiple lines in Python [duplicate]
...by using Python's implied line
continuation inside parentheses, brackets and braces. If necessary, you
can add an extra pair of parentheses around an expression, but sometimes
using a backslash looks better. Make sure to indent the continued line
appropriately.
Example of implicit line...
Is the Javascript date object always one day off?
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Notice that Eastern Daylight Time is -4 hours and that the hours on the date you're getting back are 20.
20h + 4h = 24h
which is midnight of 2011-09-24. The date was parsed in UTC (GMT) because you provided a date-only string without any time zone indicator. If you had ...
Reading/writing an INI file
Is there any class in the .NET framework that can read/write standard .ini files:
16 Answers
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PHP random string generator
I'm trying to create a randomized string in PHP, and I get absolutely no output with this:
59 Answers
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'Incomplete final line' warning when trying to read a .csv file into R
I'm trying to read a .csv file into R and upon using this formula:
15 Answers
15
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