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Delete column from pandas DataFrame
...lass, then a = A(); del a.var works just fine...
– dwanderson
Oct 4 '16 at 14:24
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@dwanderson t...
Should I use the datetime or timestamp data type in MySQL?
Would you recommend using a datetime or a timestamp field, and why (using MySQL)?
39 Answers
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ORA-30926: unable to get a stable set of rows in the source tables
...cified in USING clause. This probably means that TABLE_A is a parent table and the same ROWID is returned several times.
You could quickly solve the problem by using a DISTINCT in your query (in fact, if 'Y' is a constant value you don't even need to put it in the query).
Assuming your query is co...
How to change my Git username in terminal?
I was pushing and pulling from git in Terminal then I changed my username on github.com. I went to push some changes and it couldn't push because it was still recognizing my old username.. How do I change/update my username on git in terminal?
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Check if object is file-like in Python
...ts are objects in Python that behave like a real file, e.g. have a read() and a write method(), but have a different implementation. It is and realization of the Duck Typing concept.
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Do on-demand Mac OS X cloud services exist, comparable to Amazon's EC2 on-demand instances? [closed]
Amazon's EC2 service offers a variety of Linux and Windows OS choices, but I haven't found a service offering a similar "rent by the hour" service for a remote Mac OS X virtual machine. Does such a service exist? (iCloud looks to be just a data storage service, rather than a service allowing remot...
What is Scala's yield?
I understand Ruby and Python's yield. What does Scala's yield do?
9 Answers
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Why does GCC generate 15-20% faster code if I optimize for size instead of speed?
I first noticed in 2009 that GCC (at least on my projects and on my machines) have the tendency to generate noticeably faster code if I optimize for size ( -Os ) instead of speed ( -O2 or -O3 ), and I have been wondering ever since why.
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How to move files from one git repo to another (not a clone), preserving history
...ory, since you wanted to end up with only a (renamed) subset of the files, and this by definition changes the hashes. Since none of the standard commands (e.g. pull) rewrite history, there's no way you could use them to accomplish this.
You could refine the details, of course - some of your cloning...
Condition within JOIN or WHERE
...al algebra allows interchangeability of the predicates in the WHERE clause and the INNER JOIN, so even INNER JOIN queries with WHERE clauses can have the predicates rearrranged by the optimizer so that they may already be excluded during the JOIN process.
I recommend you write the queries in the mo...