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select and update database record with a single queryset
How do I run an update and select statements on the same queryset rather than having to do two queries:
- one to select the object
- and one to update the object
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How to start two threads at “exactly” the same time
The threads should start at same split second. I understand, if you do thread1.start() , it will take some milliseconds before the next execution of thread2.start() .
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Include all existing fields and add new fields to document
...dd a new field and include all existing fields, without having to list all the existing fields.
6 Answers
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How do I get into a non-password protected Java keystore or change the password?
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Yea thanks. What a terrible default password. I couldn't figure out what it was either. I just deleted the cacerts file and replaced it with my own.
– HeyWatchThis
Aug 15 '12 at 23:37
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How to refresh an IFrame using Javascript?
I have a webpage with an IFrame and a Button, once the button is pressed I need the IFrame to be refreshed. Is this possible, if so how? I searched and could not find any answers.
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Let JSON object accept bytes or let urlopen output strings
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HTTP sends bytes. If the resource in question is text, the character encoding is normally specified, either by the Content-Type HTTP header or by another mechanism (an RFC, HTML meta http-equiv,...).
urllib should know how to encode the bytes to...
Functional programming - is immutability expensive? [closed]
...c complexity but it’s a measurable factor.
A third disadvantage is somewhat hidden: unlike the “in-place” variant, this implementation continually requests memory from the heap for the cons cells of the list and potentially scatters memory all over the place. As a result, this algorithm has ...
Count number of rows within each group
I have a dataframe and I would like to count the number of rows within each group. I reguarly use the aggregate function to sum data as follows:
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Can someone explain the HTML5 aria-* attribute?
I wanted to know what the aria-* attributes are used for. What values can they have, and are they defined values or can I create my own values?
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Set the value of an input field
How would you set the default value of a form <input> text field in JavaScript?
14 Answers
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