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What is a “Bitmap heap scan” in a query plan?
...ee also the wikipedia article.
In short, it's a bit like a seq scan. The difference is that, rather than visiting every disk page, a bitmap index scan ANDs and ORs applicable indexes together, and only visits the disk pages that it needs to.
This is different from an index scan, where the index is...
What does status=canceled for a resource mean in Chrome Developer Tools?
...roblem where Chrome was canceling requests to load things within frames or iframes, but only intermittently and it seemed dependent on the computer and/or the speed of the internet connection.
This information is a few months out of date, but I built Chromium from scratch, dug through the source to...
jQuery posting JSON
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'data' should be a stringified JavaScript object:
data: JSON.stringify({ "userName": userName, "password" : password })
To send your formData, pass it to stringify:
data: JSON.stringify(formData)
Some servers also require the application/json c...
Remove menu and status bars in TinyMCE 4
...u can also customise what parts of the default menu bar are visible by specifying a string of enabled menus - e.g. menubar: 'file edit'
You can define your own menus like this:
menu : {
test: {title: 'Test Menu', items: 'newdocument'}
},
menubar: 'test'
...
ipython notebook clear cell output in code
... Using the clear_output(wait=True) will generally make the result nicer if you have clear_output inside a loop.
– Toke Faurby
Jun 8 '17 at 23:49
1
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Why can't we autowire static fields in spring?
...r. Also you cannot create several instances of a given class, each with a different dependency being injected (because the field is implicitly shared and creates global state - also evil).
share
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i...
How to split/partition a dataset into training and test datasets for, e.g., cross validation?
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If you want to split the data set once in two halves, you can use numpy.random.shuffle, or numpy.random.permutation if you need to keep track of the indices:
import numpy
# x is your dataset
x = numpy.random.rand(100, 5)
num...
Why is the parent div height zero when it has floated children
...t isn't floating (so nothing stops the height of the container being 0, as if it were empty).
Setting overflow: hidden on the container will avoid that by establishing a new block formatting context. See methods for containing floats for other techniques and containing floats for an explanation abo...
How to get access to HTTP header information in Spring MVC REST controller?
... Should mention, you'll get a 400 bad request error as a response in case if request will not contain such header. More flexible way is direct access to request headers as described in: stackoverflow.com/a/28209710/1828296
– lospejos
Jul 14 '16 at 13:43
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Encoding Javascript Object to Json string
...ncode a Javascript object into a JSON string and I am having considerable difficulties.
2 Answers
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