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How to COUNT rows within EntityFramework without loading contents?
... Can you tell me why is it different with the SelectMany? I don't understand. I do it without SelectMany but it gets really slow because I have over 20 million records. I tried the answer from Yang Zhang and works great, just wanted to know what the SelectMany does.
– mikesof...
How do I explicitly instantiate a template function?
...T] There seems to be (a lot) of confusion regarding explicit instantiation and specialization.
The code I posted above deals with explicit instantiation. The syntax for specialization is different.
Here is syntax for specialization:
template <typename T> void func(T param) {} // definition
t...
Using LIMIT within GROUP BY to get N results per group?
...T aggregated function to get all years into a single column, grouped by id and ordered by rate:
SELECT id, GROUP_CONCAT(year ORDER BY rate DESC) grouped_year
FROM yourtable
GROUP BY id
Result:
-----------------------------------------------------------
| ID | GROUPED_YEAR ...
Which $_SERVER variables are safe?
Any variable that a user can control, an attacker can also control and is therefore a source of an attack. This is called a "tainted" variable, and is unsafe.
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What is PAGEIOLATCH_SH wait type in SQL Server?
...;value> order by <PrimaryKey>. We also have an index on just col1 and have tried rebuilding the index.
– Ryan
Mar 9 '09 at 15:36
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Dependency Walker reports IESHIMS.DLL and WER.DLL missing?
...un Dependency Walker on an executable of mine it reports that:
IESHIMS.DLL and WER.DLL can't be found.
4 Answers
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OnItemCLickListener not working in listview
...then OnItemClickListener won't work.
The row item must have a param like
android:descendantFocusability = "blocksDescendants".
Here you can see an example of how your list item should look like.
Your list item xml should be...
row_item.xml (your_xml_file.xml)
<LinearLayout xmlns:android="http...
When NOT to use yield (return) [duplicate]
... this O(n) times for a tree with n items, that makes the algorithm O(hn). And since the height of a binary tree is lg n <= h <= n, that means that the algorithm is at best O(n lg n) and at worst O(n^2) in time, and best case O(lg n) and worse case O(n) in stack space. It is O(h) in heap space...
How to migrate/convert from SVN to Mercurial (hg) on windows
...to migrate a couple of SVN repositories to Mercurial, with history, labels and so on.
9 Answers
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Get the current URL with JavaScript?
...age loading I need to be able to grab the full, current URL of the website and set it as a variable to do with as I please.
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