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Android emulator shows nothing except black screen and adb devices shows “device offline”
I am just trying to start development in Android.
So, the problem is that when I try to launch an emulator by issuing the command emulator @A2 , an emulator comes up on the screen. But even after waiting for as long as 2-3 hrs, all it shows is a black screen. Not even the android home screen or t...
Drop a temporary table if it exists
...
You could also consider truncating the table instead rather than dropping and recreating.
IF OBJECT_ID('tempdb..##CLIENTS_KEYWORD', 'U') IS NOT NULL
TRUNCATE TABLE ##CLIENTS_KEYWORD
ELSE
CREATE TABLE ##CLIENTS_KEYWORD
(
client_id INT
)
...
What are the underlying data structures used for Redis?
...every Redis operation you'll find the time complexity in the documentation and, if you have the set of operations and the time complexity, the only other thing you need is some clue about memory usage (and because we do many optimizations that may vary depending on data, the best way to get these la...
mysql query order by multiple items
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Sort by picture and then by activity:
SELECT some_cols
FROM `prefix_users`
WHERE (some conditions)
ORDER BY pic_set, last_activity DESC;
share
|
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Selenium c# Webdriver: Wait Until Element is Present
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I used the approach provided and found the method was deprecated as pointed out by Samuel. Checking for the existence of an item now waits up to the specified time.
– Jim Scott
Jun 1 '17 at 0:47
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Count the number of occurrences of a character in a string in Javascript
...a regular expression literal if you know what you are searching for beforehand, if not you can use the RegExp constructor, and pass in the g flag as an argument.
match returns null with no results thus the || []
The original answer I made in 2009 is below. It creates an array unnecessarily, but us...
How to set host_key_checking=false in ansible inventory file?
I would like to use ansible-playbook command instead of ' vagrant provision '. However setting host_key_checking=false in the hosts file does not seem to work.
...
Connect Java to a MySQL database
...(DataSource) context.lookup("java:comp/env/jdbc/myDB");
or instantiating and configuring one from your database driver directly:
MysqlDataSource dataSource = new MysqlDataSource();
dataSource.setUser("scott");
dataSource.setPassword("tiger");
dataSource.setServerName("myDBHost.example.org");
an...
“int main (vooid)”? How does that work?
I recently had to type in a small C test program and, in the process, I made a spelling mistake in the main function by accidentally using vooid instead of void .
...
Access to Modified Closure (2)
...need to re-declare a variable inside the foreach - otherwise it is shared, and all your handlers will use the last string:
foreach (string list in lists)
{
string tmp = list;
Button btn = new Button();
btn.Click += new EventHandler(delegate { MessageBox.Show(tmp); });
}
Significantly,...