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Fast way to discover the row count of a table in PostgreSQL
... and counts rows in it. A bigger sample increases the cost and reduces the error, your pick. Accuracy depends on more factors:
Distribution of row size. If a given block happens to hold wider than usual rows, the count is lower than usual etc.
Dead tuples or a FILLFACTOR occupy space per block. If...
Returning multiple values from a C++ function
... put the function definition of divide into a separate cpp file? I get the error error: use of ‘auto divide(int, int)’ before deduction of ‘auto’. How do I solve this?
– Adriaan
Feb 23 '18 at 20:26
...
Render HTML to an image
... = dataUrl;
document.appendChild(img);
})
.catch(function (error) {
console.error('oops, something went wrong!', error);
});
share
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...
Set custom HTML5 required field validation message
...ment (DOM node) and it must return a string which is then displayed as the error message.
Compatibility
Tested in:
Chrome Canary 47.0.2
IE 11
Microsoft Edge (using the up-to-date version as of 28/08/2015)
Firefox 40.0.3
Opera 31.0
Old answer
You can see the old revision here: https://stacko...
Accessing console and devtools of extension's background.js
...tensions and I can't seem to log to console from my background js. When an error occurs (because of a syntax error, for example), I can't find any error messages either.
...
Creating an abstract class in Objective-C
...NSInvalidAbstractInvocation(). Calling an abstract method is a programming error, which is why it throws an exception. Abstract factories are commonly implemented as class clusters.
– quellish
Aug 2 '14 at 23:40
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Why does Ruby have both private and protected methods?
... # true
gimli.name # 'Gimli'
gimli.age # NoMethodError: private method `age'
called for #<Dwarf:0x007ff552140128>
gimli.beard_strength # NoMethodError: protected method `beard_strength'
called for #<Dwarf:0x007ff552...
How to set environment variables in Python?
...EBUSSY'] = str(myintvariable)
then for retrieval, consider that to avoid errors, you should try
os.environ.get('DEBUSSY', 'Not Set')
possibly substitute '-1' for 'Not Set'
so, to put that all together
myintvariable = 1
os.environ['DEBUSSY'] = str(myintvariable)
strauss = int(os.environ.get('S...
Finding local IP addresses using Python's stdlib
...
It might be a good idea to catch socket.error exceptions which may be risen by s.connect()!
– phobie
Oct 14 '11 at 14:52
40
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jQuery append() - return appended elements
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This will throw an error if newHtml is not valid HTML or a valid jQuery selector: $('/ This is Not HTML /').appendTo('#myDiv') results in Uncaught Error: Syntax error, unrecognized expression while $('#myDiv').append('/ This is Not HTML /') wor...