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Inheriting from a template class in c++
...e way you speak about them determines the way to think about them.
Specifically, Area is not a template class, but a class template. That is, it is a template from which classes can be generated. Area<int> is such a class (it's not an object, but of course you can create an object from that c...
How to pass a user defined argument in scrapy spider
...d. Python throws a not defined error. BTW, why have you omitted the super call? PS. I'm working with the CrawlSpider class
– Birla
Sep 24 '14 at 10:57
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HTML input file selection event not firing upon selecting the same file
... the value of file control to blank string.so the .change() will always be called even the file name changes or not. like for example you can do this thing and worked for me like charm
$('#myFile').change(function () {
LoadFile("myFile");//function to do processing of file.
$('#myF...
find vs find_by vs where
...its your needs best.
The find method is usually used to retrieve a row by ID:
Model.find(1)
It's worth noting that find will throw an exception if the item is not found by the attribute that you supply. Use where (as described below, which will return an empty array if the attribute is not foun...
A migration to add unique constraint to a combination of columns
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The problem with the model level validation is that it doesn't scale. Two servers could run the same data through at the same time (like a double tap on an api heavy app) I have two identical records in my DB right now and the model has the validation..
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Define variable to use with IN operator (T-SQL)
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DECLARE @mylist TABLE (Id int)
INSERT INTO @mylist
SELECT id FROM (VALUES (1),(2),(3),(4),(5)) AS tbl(id)
SELECT * FROM Mytable WHERE theColumn IN (select id from @mylist)
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Aligning textviews on the left and right edges in Android layout
I am getting started with Android. I am having trouble getting a simple layout going.
9 Answers
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Center/Set Zoom of Map to cover all visible Markers?
I am setting multiple markers on my map and I can set statically the zoom levels and the center but what I want is, to cover all the markers and zoom as much as possible having all markets visible
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SQL WHERE condition is not equal to?
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You can do like this
DELETE FROM table WHERE id NOT IN ( 2 )
OR
DELETE FROM table WHERE id <> 2
As @Frank Schmitt noted, you might want to be careful about the NULL values too. If you want to delete everything which is not 2(including the NULLs) then add O...