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Facebook database design?
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Keep a friend table that holds the UserID and then the UserID of the friend (we will call it FriendID). Both columns would be foreign keys back to the Users table.
Somewhat useful example:
Table Name: User
Columns:
UserID PK
EmailAddress
Password
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MongoDB SELECT COUNT GROUP BY
...er way to do it using aggregate:
db.contest.aggregate([
{"$group" : {_id:"$province", count:{$sum:1}}}
])
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Can I define a class name on paragraph using Markdown?
...arkdown?
Natively? No. But...
No, Markdown's syntax can't. You can set ID values with Markdown Extra through.
You can use regular HTML if you like, and add the attribute markdown="1" to continue markdown-conversion within the HTML element. This requires Markdown Extra though.
<p class='spec...
MenuItemCompat.getActionView always returns null
...ry but the MenuItemCompat.getActionView always return null in every Android version I tested (4.2.2, 2.3.4 ....)
11 Answe...
JOIN queries vs multiple queries
...ins, multiple queries is much better... look at the following benchmark I did:
Single query with 5 Joins
query: 8.074508 seconds
result size: 2268000
5 queries in a row
combined query time: 0.00262 seconds
result size: 165 (6 + 50 + 7 + 12 + 90)
.
Note that we get the same results in both ...
How to put Google Maps V2 on a Fragment using ViewPager
...I got to display the tab layout using a fragments and viewpager from androidhive. However, I can't implement google maps v2 on it. I searched the internet for hours already, but I can't find a tutorial on how to do it. Can some one please show me how?
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Using a ListAdapter to fill a LinearLayout inside a ScrollView layout
...mething like this (no ScrollView needed anymore):
<ListView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/my_top_layout"
android:layout_width="fill_parent"
android:layout_height="fill_parent"/>
Then in onCreateView() (I'll use an example with a fragment) ...
Split a List into smaller lists of N size
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@HaraldCoppoolse the OP didn't ask for selecting, only to split lists
– Phate01
Mar 22 '18 at 16:11
1
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How do you join on the same table, twice, in mysql?
I have 2 tables. One (domains) has domain ids, and domain names (dom_id, dom_url).
3 Answers
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Best practice: AsyncTask during orientation change
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Do NOT use android:configChanges to address this issue. This is very bad practice.
Do NOT use Activity#onRetainNonConfigurationInstance() either. This is less modular and not well-suited for Fragment-based applications.
You can read my art...