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MySQL error: key specification without a key length
I have a table with a primary key that is a varchar(255). Some cases have arisen where 255 characters isn't enough. I tried changing the field to a text, but I get the following error:
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How to force use of overflow menu on devices with menu button
I'd like to have all of the menu items that don't fit into the ActionBar go into the overflow menu (the one that is reached from the Action Bar not the menu button) even on devices that do have a Menu button . This seems much more intuitive for users than throwing them into a separate menu list th...
How do I provide JVM arguments to VisualVM?
...26 to profile a Java webapp running under Tomcat, but VisualVM often tells me that it doesn't have enough memory to take a snapshot, and to use the -Xmx switch to provide more memory to Netbeans. The problem is, I'm running VisualVM outside of Netbeans, so how can I provide JVM arguments to jvisualv...
d3 axis labeling
...component, but you can add labels yourself simply by adding an SVG text element. A good example of this is my recreation of Gapminder’s animated bubble chart, The Wealth & Health of Nations. The x-axis label looks like this:
svg.append("text")
.attr("class", "x label")
.attr("text-anc...
Embedding SVG into ReactJS
...ty with current browser support for SVG (source). You just need to apply some syntax transformations to make it JSX compatible, like you already have to do for HTML (class → className, style="color: purple" → style={{color: 'purple'}}). For any namespaced (colon-separated) attribute, e.g. xlink:...
Left-pad printf with spaces
...t's one way you can do it).
If you know you want exactly 40 spaces then some text, just save the 40 spaces in a constant and print them. If you need to print multiple lines, either use multiple printf statements like the one above, or do it in a loop, changing the value of ptr each time.
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MIN/MAX vs ORDER BY and LIMIT
Out of the following queries, which method would you consider the better one? What are your reasons (code efficiency, better maintainability, less WTFery)...
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Embedding Python in an iPhone app
...code, for example -- but what does matter is the product of that build.
Namely, you are going to need to build something like libPython.a that can be statically linked into your application. Once you have a .a, that can be added to the Xcode project for your application(s) and, from there, it'll b...
How do I allow HTTPS for Apache on localhost?
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I've just attempted this - I needed to test some development code on my localhost Apache on Windows. This was WAAAY more difficult than it should be. But here are the steps that managed to work after much hairpulling...
I found that my Apache install comes with openss...
How to write asynchronous functions for Node.js
...s functions should be written. After a lot of plowing through a lot of documentation, it's still unclear to me.
6 Answers
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