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How to deal with “java.lang.OutOfMemoryError: Java heap space” error?
...h performance code.
Use local variables wherever possible.
Make sure you select the correct object (EX: Selection between String, StringBuffer and StringBuilder)
Use a good code system for your program(EX: Using static variables VS non static variables)
Other stuff which could work on your code.
T...
View contents of database file in Android Studio
...File Explorer (one of the tabs on the right), go to /data/data/databases
Select the database by just clicking on it.
Go to the top right corner of the Android Device Monitor window. Click on the 'pull a file from the device' button:
A window will open asking you where you want to save your data...
How to select the rows with maximum values in each group with dplyr? [duplicate]
I would like to select a row with maximum value in each group with dplyr.
6 Answers
6
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PostgreSQL, checking date relative to “today”
...
select * from mytable where mydate > now() - interval '1 year';
If you only care about the date and not the time, substitute current_date for now()
...
Are Stored Procedures more efficient, in general, than inline statements on modern RDBMS's? [duplica
...he query plan that is generated is sub-optimal.
For example, if you send SELECT *
FROM table WHERE id BETWEEN 1 AND
99999999, the DBMS may select a
full-table scan instead of an index
scan because you're grabbing every row
in the table (so sayeth the
statistics). If this is the cached
...
Delete all the queues from RabbitMQ?
...oto Policies tab(on the right side)
Add Policy
Fill Fields
Virtual Host: Select
Name: Expire All Policies(Delete Later)
Pattern: .*
Apply to: Queues
Definition: expires with value 1 (change type from String to Number)
Save
Checkout Queues tab again
All Queues must be deleted
And don't forget remo...
Connect to Amazon EC2 file directory using Filezilla and SFTP
...SFTP, Click "Add key file”
Browse to the location of your .pem file and select it.
A message box will appear asking your permission to convert the file into ppk format. Click Yes, then give the file a name and store it somewhere.
If the new file is shown in the list of Keyfiles, then continue t...
Why does installing Nokogiri on Mac OS fail with libiconv is missing?
...ed to install xCode command tools to allow you to install libiconv.
xcode-select --install
then install a newer version of libiconv
brew install libiconv
then install your gem
gem install nokogiri -- --with-iconv-dir=/usr/local/Cellar/libiconv/1.14
...
How to change package name of Android Project in Eclipse?
...can rename or change the package name, and also by right-clicking and then select Rename option, you can change or rename the package name.
When you press F2, it will show you the dialog box as:
In this dialog, don't forget to check the "Update references" checkbox because by making "check" to t...
Possible to iterate backwards through a foreach?
...inq can help you.
A Linq extension method using anonymous types with Linq Select to provide a sorting key for Linq OrderByDescending;
public static IEnumerable<T> Invert<T>(this IEnumerable<T> source)
{
var transform = source.Select(
(o, i) => new
...