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How can you hide database output in Rails console?
...how/why your post will solve the problem.
– Mick MacCallum
Oct 6 '12 at 6:35
7
This is going to s...
Filtering for empty or NULL names in a queryset
...lias (optional) which I need to search for. So, I need a query to give me all the names that have an alias set.
7 Answers
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Postgres: “ERROR: cached plan must not change result type”
...after the database table was modified. This reset the database connection, allowing the prepared statement to execute without errors.
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How can I get the sha1 hash of a string in node.js?
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Good idea. Note, however, that all objects (except arrays and null) will have the same sha1sum value since Object.toString() returns [object Object] by default. So sha1sum({}) === sha1sum({"foo":"bar"}) === sha1sum({"a":1}), etc.
– m...
How can I filter lines on load in Pandas read_csv function?
...ec]:
filtered = df[(df['timestamp'] > targettime)]
This is selecting all rows in df (assuming df is any DataFrame, such as the result of a read_csv call, that at least contains a datetime column timestamp) for which the values in the timestamp column are greater than the value of targettime. S...
Where does the “flatmap that s***” idiomatic expression in Scala come from?
...t you can replace a lot of tedious if/then/else code you would write with calls to flatMap (and other higher order functions).
This is especially true for Options (see http://tonymorris.github.io/blog/posts/scalaoption-cheat-sheet/)
But it applies to other monads as well (although I have to admit...
Does a valid XML file require an XML declaration?
... It even goes on to state that if the declaration is absent, that automatically implies the document is an XML 1.0 document.
Note that in an XML Declaration the encoding and standalone are both optional. Only the version is mandatory. Also, these are not attributes, so if they are present they must...
What is the reason for performing a double fork when creating a daemon?
... by setsid(). So, the first forked process becomes a session leader after calling setsid() and then we fork again so that the final, double-forked process is no longer a session leader. Other than the requirement of setsid() to be a session leader, you are spot on.
– dbmikus
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Bash continuation lines
... like a single string which crosses lines, while indenting but not getting all those spaces, one approach you can try is to ditch the continuation line and use variables:
$ a="continuation"
$ b="lines"
$ echo $a$b
continuationlines
This will allow you to have cleanly indented code at the expense ...
Should I use SVN or Git? [closed]
...r. It's decentralised to a point where people can track their own edits locally without having to push things to an external server.
SVN is designed to be more central where Git is based on each user having their own Git repo and those repos push changes back up into a central one. For that reason,...