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Get the latest record from mongodb collection
...oDB are B-Trees. Searching a B-Tree is a O(logN) operation, so even find({_id:...}) will not provide constant time, O(1) responses.
That stated, you can also sort by the _id if you are using ObjectId for you IDs. See here for details. Of course, even that is only good to the last second.
You may t...
Android: How to bind spinner to custom object list?
...hich contains some names (the names are visible) and each name has its own ID (the IDs are not equal to display sequence). When the user selects the name from the list the variable currentID has to be changed.
...
How to remove item from list in C#?
...ou can use Remove(T item):
var itemToRemove = resultlist.Single(r => r.Id == 2);
resultList.Remove(itemToRemove);
When you are not sure the item really exists you can use SingleOrDefault. SingleOrDefault will return null if there is no item (Single will throw an exception when it can't find th...
In which order do CSS stylesheets override?
...REC-CSS2-20110607/cascade.html#cascade
In short: more specific rules override more general ones. Specificity is defined based on how many IDs, classes, and element names are involved, as well as whether the !important declaration was used. When multiple rules of the same "specificity level" exist, ...
How to define two fields “unique” as couple
...= ('field1', 'field2',)
And in your case:
class Volume(models.Model):
id = models.AutoField(primary_key=True)
journal_id = models.ForeignKey(Journals, db_column='jid', null=True, verbose_name = "Journal")
volume_number = models.CharField('Volume Number', max_length=100)
comments = models....
SQL - find records from one table which don't exist in another
... WHERE Phone_book.phone_number IS NULL
(ignoring that, as others have said, it's normally best to select just the columns you want, not '*')
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Scroll to a div using jquery
so I have a page that has a fixed link bar on the side. I'd like to scroll to the different divs. Basically the page is just one long website, where I'd like to scroll to different divs using the menu box to the side.
...
SQL Server equivalent to Oracle's CREATE OR REPLACE VIEW
...rocedures as follows.
IF NOT EXISTS (SELECT * FROM sys.views WHERE object_id = OBJECT_ID(N'[dbo].[vw_myView]'))
EXEC sp_executesql N'CREATE VIEW [dbo].[vw_myView] AS SELECT ''This is a code stub which will be replaced by an Alter Statement'' as [code_stub]'
GO
ALTER VIEW [dbo].[vw_myView]
AS
S...
How to add leading zeros?
...igits to begin with, so let's try a harder example of making powers of 10 width 8 too.
anim <- 25499:25504
x <- 10 ^ (0:5)
paste (and it's variant paste0) are often the first string manipulation functions that you come across. They aren't really designed for manipulating numbers, but the...
Android ViewPager with bottom dots
...ewpager with tablayout.
Your main Layout:
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<android.support.v4.view.ViewPag...