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JOIN two SELECT statement results
Is it possible to join the results of 2 sql SELECT statements in one statement?
I have a database of tasks where each record is a separate task, with deadlines (and a PALT , which is just an INT of days from start to deadline. Age is also an INT number of days.)
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MySQL: Fastest way to count number of rows
...s.
The solution is SQL_CALC_FOUND_ROWS. This is usually used when you are selecting rows but still need to know the total row count (for example, for paging).
When you select data rows, just append the SQL_CALC_FOUND_ROWS keyword after SELECT:
SELECT SQL_CALC_FOUND_ROWS [needed fields or *] FROM t...
Using Linq to get the last N elements of a collection?
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You can solve this problem by explicitly casting mystring to IEnumerable<String>: ((IEnumerable<String>)mystring).Reverse().Take(2).Reverse()
– Jan Hettich
Aug 17 '11 at 18:08
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How to find if a given key exists in a C++ std::map
... @jv110 The Microsoft C++ compiler issues a warning when it encounters a cast from int to bool. Though there are other C++ compilers that do not issue a similar warning, I prefer using an explicit comparison to make the intent clear and enhance readability. Note that other languages such as C# for...
Search for selection in vim
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Check this Vim tip: Search for visually selected text
Or you can simply yank the selected text with y and go to search mode /, then you can paste the last yanked text with Ctrl+R 0
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Html.DropdownListFor selected value not being set
How can I set the selected value of a Html.DropDownListFor? I've been having a look online and have seen that it can be achieved by using the fourth parameter so like the below:
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Background task, progress dialog, orientation change - is there any 100% working solution?
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Step #5: In onCreate(), if getLastNonConfigurationInstance() is not null, cast it to your AsyncTask class and call your setter to associate your new activity with the task.
Step #6: Do not refer to the activity data member from doInBackground().
If you follow the above recipe, it will all work. o...
String concatenation vs. string substitution in Python
...ou are profiling how. For one your concat is slow because you have two str casts in it. With strings the result is the opposite, since string concat is actually faster than all the alternatives when only three strings are concerned.
– Justus Wingert
Sep 16 '15 ...
MySQL select with CONCAT condition
...available within the query itself.
You can either repeat the expression:
SELECT neededfield, CONCAT(firstname, ' ', lastname) as firstlast
FROM users
WHERE CONCAT(firstname, ' ', lastname) = "Bob Michael Jones"
or wrap the query
SELECT * FROM (
SELECT neededfield, CONCAT(firstname, ' ', last...
Difference between a Structure and a Union
...ome_test_pointer;
some_test_pointer can point to int* or double*. If you cast an address of type test to int*, it will point to its first member, a, actually. The same is true for an union too. Thus, because an union will always have the right alignment, you can use an union to make pointing to so...