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MySQL, Check if a column exists in a table with SQL
... query that will check if a specific table in MySQL has a specific column, and if not — create it. Otherwise do nothing. This is really an easy procedure in any enterprise-class database, yet MySQL seems to be an exception.
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Add UIPickerView & a Button in Action sheet - How?
...ext errors in iOS 7. I just spent a few hours working through this problem and ultimately decided to take a different approach. I replaced the call to show the action sheet with a modal view controller containing a simple tableview.
There are many ways to accomplish this. Here's one way that I jus...
How do CSS triangles work?
...ere're plenty of different CSS shapes over at CSS Tricks - Shapes of CSS and I'm particularly puzzled with a triangle:
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Why were pandas merges in python faster than data.table merges in R in 2012?
I recently came across the pandas library for python, which according to this benchmark performs very fast in-memory merges. It's even faster than the data.table package in R (my language of choice for analysis).
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Git Blame Commit Statistics
How can I "abuse" blame (or some better suited function, and/or in conjunction with shell commands) to give me a statistic of how much lines (of code) are currently in the repository originating from each committer?
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On localhost, how do I pick a free port number?
I'm trying to play with inter-process communication and since I could not figure out how to use named pipes under Windows I thought I'll use network sockets. Everything happens locally. The server is able to launch slaves in a separate process and listens on some port. The slaves do their work and s...
Test whether string is a valid integer
...l script. If the user provided a valid integer, the script does one thing, and if not valid, it does something else. Trouble is, I haven't found an easy (and reasonably elegant) way of doing this - I don't want to have to pick it apart char by char.
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Detail change after Git pull
... branches, with an asterisk by the currently checked-out one, with the command git branch. The current branch name is also printed along with the output of git status. I highly recommend skimming the man pages of commands to use - it's a great way to slowly pick up some knowledge.
And your last que...
Build android release apk on Phonegap 3.x CLI
How can I build an android app locally using the Phonegap 3.x CLI, ready to release? I check the bin folder generated inside the platforms/android directory of the project, and only has .debug APKs.
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Elastic Search: how to see the indexed data
I had a problem with ElasticSearch and Rails, where some data was not indexed properly because of attr_protected. Where does Elastic Search store the indexed data? It would be useful to check if the actual indexed data is wrong.
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