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Why would someone use WHERE 1=1 AND in a SQL clause?
Why would someone use WHERE 1=1 AND <conditions> in a SQL clause (Either SQL obtained through concatenated strings, either view definition)
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How to compare two floating point numbers in Bash?
...) )); then
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fi
Explanation
Piping through the basic calculator command bc returns either 1 or 0.
The option -l is equivalent to --mathlib; it loads the standard math library.
Enclosing the whole expression between double parenthesis (( )) will translate these values to respectively true or...
Format JavaScript date as yyyy-mm-dd
...eformatting a date string should not depend on successful parsing of non-standard strings by the built-in parser. Given the OP format, it can be reformatted in less code without using a Date at all.
– RobG
Jun 16 '17 at 12:12
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How do you serve a file for download with AngularJS or Javascript?
...omatically when the document is unloaded; however, for optimal performance and memory usage, if there are safe times when you can explicitly unload them, you should do so.
Source: MDN
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How to check if a string is a valid JSON string in JavaScript without using Try/Catch
...t, read the answer below.
Here we just check a JSON string using a regexp, and it will work in most cases, not all cases.
Have a look around the line 450 in https://github.com/douglascrockford/JSON-js/blob/master/json2.js
There is a regexp that check for a valid JSON, something like:
if (/^[\],:{...
qmake: could not find a Qt installation of ''
... qt5base-dev qtdeclarative5-dev qt5-qmake qt5-default qttools5-dev-tools And then check using: qtchooser -print-env
– Salil
Jan 25 '16 at 23:42
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Create nice column output in python
I am trying to create a nice column list in python for use with commandline admin tools which I create.
18 Answers
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Add column with constant value to pandas dataframe [duplicate]
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The reason this puts NaN into a column is because df.index and the Index of your right-hand-side object are different. @zach shows the proper way to assign a new column of zeros. In general, pandas tries to do as much alignment of indices as possible. One downside is that when indice...
Why would json_encode return an empty string
...conv() or mb_convert_encoding() may be better options as noted in comments and other solutions.
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How do I use .toLocaleTimeString() without displaying seconds?
...{hour: '2-digit', minute:'2-digit'});
Supported by Firefox, Chrome, IE9+ and Opera. Try it on your web browser console.
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