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How to COUNT rows within EntityFramework without loading contents?
... where o.ID == '1'
from t in o.MyTable
select t).Count();
Method syntax:
var count = context.MyContainer
.Where(o => o.ID == '1')
.SelectMany(o => o.MyTable)
.Count()
Both generate the same SQL query.
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Pandas selecting by label sometimes return Series, sometimes returns DataFrame
In Pandas, when I select a label that only has one entry in the index I get back a Series, but when I select an entry that has more then one entry I get back a data frame.
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App Inventor 2 ColorUtilities 拓展：#ececec 等16进制颜色转换为AppInven...
...% auto no-repeat; } /*手机版：反馈浮动按钮收小*/ @media screen and (max-width: 700px) { .feedback-pop { font-size: 13px; line-height: 14px; padding: 10px 7px; } .feedback-pop .feedback-img { width: 20px; height: 20px; margin-bottom: 3px; } } 文档反馈 切...
django : using select_related and get_object_or_404 together
Is there any way of using get_object_or_404 and select_related together or any other way to achieve the result of using these two together(except from putting it in try/except)??
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Random record from MongoDB
...llection.
db.mycoll.aggregate([{ $sample: { size: 1 } }])
If you want to select the random document(s) from a filtered subset of the collection, prepend a $match stage to the pipeline:
// Get one random document matching {a: 10} from the mycoll collection.
db.mycoll.aggregate([
{ $match: { a:...
Comparing date ranges
... range_start, here's some simple SQL to retrieve all the matching rows:
SELECT *
FROM periods
WHERE NOT (range_start > @check_period_end
OR range_end < @check_period_start)
Note the NOT in there. Since the two simple rules finds all the non-matching rows, a simple NOT will reve...
View more than one project/solution in Visual Studio
... With multiple projects, if I have multiple main() methods, how do I select which I want to have compiled?
– 5Daydreams
Aug 11 at 16:12
add a comment
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How to automatically navigate to the current class in Intellij Idea Project Tool Window?
...expands to show the currently open class (or file), and this class becomes selected in the tree.
6 Answers
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for each loop in Objective-C for accessing NSMutable dictionary
I am finding some difficulty in accessing mutable dictionary keys and values in Objective-C.
7 Answers
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Troubleshooting “Illegal mix of collations” error in mysql
Am getting the below error when trying to do a select through a stored procedure in MySQL.
16 Answers
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