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Get distance between two points in canvas
I have canvas drawing tab and want lineWidth to be based on distance between two last mousemove coordinate updates. I will make translation of distance to width myself, I just need to know how to get distance between those points (I already have coordinates of those pointes).
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How to debug Lock wait timeout exceeded on MySQL?
...nnoDB tables.
Since you know the query, all the tables being accessed are candidates for being the culprit.
From there, you should be able to run SHOW ENGINE INNODB STATUS\G
You should be able to see the affected table(s)
You get all kinds of additional Locking and Mutex Information.
Here is a sampl...
Unable to forward search Bash history similarly as with CTRL-r
...earch forward as well. From the bash info manual, "8.2.5 Searching for Commands in the History":
To search backward in the history for a particular string, type C-r.
Typing C-s searches forward through the history.
The problem with Ctrl-S however is that sometimes collides with XON/XOFF flow...
How to display unique records from a has_many through relationship?
...ct => "DISTINCT products.*). In the first case, ALL records are fetched and rails removes the duplicates for you. In the later case, only non-duplicate records are fetched from the db so it might offer better performance if you have a large result set.
– mbreining
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How can I propagate exceptions between threads?
... Sep 6 '15 at 21:22
Gerardo HernandezGerardo Hernandez
1,4301313 silver badges1919 bronze badges
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Exporting data In SQL Server as INSERT INTO
I am using SQL Server 2008 Management Studio and have a table I want to migrate to a different db server.
11 Answers
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Is it possible to force ignore the :hover pseudoclass for iPhone/iPad users?
I have some css menus on my site that expand with :hover (without js)
15 Answers
15
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What does = +_ mean in JavaScript
...page on Arithmetic Operators:
The unary plus operator precedes its operand and evaluates to its
operand but attempts to converts it into a number, if it isn't
already. [...] It can convert string representations of integers and
floats, as well as the non-string values true, false, and null...
Changing image size in Markdown
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With certain Markdown implementations (including Mou and Marked 2 (only macOS)) you can append =WIDTHxHEIGHT after the URL of the graphic file to resize the image. Do not forget the space before the =.
You can skip the HEIGHT
![](./pic/pic1s.p...
CSS Div stretch 100% page height
I have a navigation bar on the left hand side of my page, and I want it to stretch to 100% of the page height. Not just the height of the viewport, but including the areas hidden until you scroll. I don't want to use javascript to accomplish this.
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