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How to query as GROUP BY in django?
...nnotate(dcount=Count('designation'))
This results in a query similar to
SELECT designation, COUNT(designation) AS dcount
FROM members GROUP BY designation
and the output would be of the form
[{'designation': 'Salesman', 'dcount': 2},
{'designation': 'Manager', 'dcount': 2}]
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Parsing huge logfiles in Node.js - read in line-by-line
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'line-by-line' is more memory efficient than the selected answer. For 1 million lines in a csv the selected answer had my node process in the low 800s of megabytes. Using 'line-by-line' it was consistently in the low 700s. This module also keeps the code clean and easy to r...
How can I change the copyright template in Xcode 4?
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Xcode 4 (and above) stores this on a per-project basis.
If you select the project in the Project Navigator (Cmd-1) and open the File Inspector (Cmd-Opt-1), you'll see a field for "Organization" under "Project Document".
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AngularJS - Multiple ng-view in single template
...the content. Here assume you have one main ng-view and instead of manually selecting sub content by selecting drop down, you do it as when main view is loaded.
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What exactly is nullptr?
...rloading a function for both pointers and integers, and passing nullptr to select the pointer version. Passing NULL or 0 would confusingly select the int version.
A cast of nullptr_t to an integral type needs a reinterpret_cast, and has the same semantics as a cast of (void*)0 to an integral type (...
What does a space mean in a CSS selector? i.e. What is the difference between .classA.classB and .cl
What is the difference between these two selectors?
3 Answers
3
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presentViewController:animated:YES view will not appear until user taps again
...ese sources. I've found the issue by using a UITableViewCell which had its selectionStyle set to UITableViewCellSelectionStyleNone, so that no selection animation triggered the runloop after the row selection handler ran.
To fix it (until Apple does something) you can trigger the main runloop by s...
Setting up foreign keys in phpMyAdmin?
..._id, in your case). Then, go to relation view (in the referring table) and select the referred column (so in your case foo.id) and the on update and on delete actions.
I think foreign keys are useful if you have multiple tables linked to one another, in particular, your delete scripts will become v...
Aggregate / summarize multiple variables per group (e.g. sum, mean)
...-date), sum)
# summarising a specific set of non-grouping variables using select_helpers
# see ?select_helpers for more options
df2 <- df1 %>% group_by(year, month) %>% summarise_at(vars(starts_with('x')), sum)
df2 <- df1 %>% group_by(year, month) %>% summarise_at(vars(matches('.*...
Changing Ctrl + Tab behavior for moving between documents in Visual Studio
...w place cursor in the Press shortcut keys: textbox (doesn't matter what is selected currently, you're not going to Assign this time), and type first of the three (or two or one) shortcuts.
You'll see Shortcut currently used by: listed. Ensure that you have no duplicate entry for the shortcut. In...