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Why is using a wild card with a Java import statement bad?
...h cleaner to import entire packages; the issues identified here (e.g. java.sql.Date vs java.util.Date) are easily remedied by other means, not really addressed by specific imports and certainly do not justify insanely pedantic imports on all classes. There is nothing more disconcerting than opening...
How to get year, month, day, hours, minutes, seconds and milliseconds of the current moment in Java?
....text.SimpleDateFormat:
Date now = new Date(); // java.util.Date, NOT java.sql.Date or java.sql.Timestamp!
String format1 = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS", Locale.ENGLISH).format(now);
String format2 = new SimpleDateFormat("EEE, d MMM yyyy HH:mm:ss Z", Locale.ENGLISH).format(now);
...
How to move out of auto-completed brackets in IntelliJ IDEA (without using the arrow keys)?
...visual indication of tab 'exit' position. For now, it should work in Java, SQL, Python and some other files. It will take some time for other languages to catch up - some language-specific code changes are required.
The feature is disabled by default, you can enable it in
Settings -> Edito...
Why is SELECT * considered harmful?
...ich was which? SELECT * can also confuse views (at least in some versions SQL Server) when underlying table structures change -- the view is not rebuilt, and the data which comes back can be nonsense. And the worst part of it is that you can take care to name your columns whatever you want, but th...
How to verify if a file exists in a batch file?
...ndler echo Now Exiting && Exit
if not exist C:\myprogram\html\data.sql Exit
We will take those three files and put it in a temporary place. After deleting the folder, it will restore those three files.
xcopy "test" "C:\temp"
xcopy "test2" "C:\temp"
del C:\myprogram\sync\
xcopy "C:\temp" "...
Overriding a Rails default_scope
... like: def self.random; unscoped.order('rand()'); end unscoped removes ALL sql before it, not just what is listed under default_scope. While technically a correct answer, be careful using unstopped
– Schneems
Dec 25 '11 at 21:58
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Retrieving the last record in each group - MySQL
...
MySQL 8.0 now supports windowing functions, like almost all popular SQL implementations. With this standard syntax, we can write greatest-n-per-group queries:
WITH ranked_messages AS (
SELECT m.*, ROW_NUMBER() OVER (PARTITIO...
In MySQL queries, why use join instead of where?
...d
From a Performance Perspective:
Where supported (Oracle 9i+, PostgreSQL 7.2+, MySQL 3.23+, SQL Server 2000+), there is no performance benefit to using either syntax over the other. The optimizer sees them as the same query. But more complex queries can benefit from using ANSI-92 syntax:
A...
Create a new database with MySQL Workbench
Being new to MySQL, I have installed the latest version of the MySQL Workbench (5.2.33). I would like to know how you can create a database with this application. In the Overview tab of the SQL editor there are few "MySQL Schema" displayed, are these schemas the existing databases?
...
MySQL root password change
I have been trying to reset my MySQL root password. I have run the mysqld_safe --skip-grant-tables, updated the root password, and checked the user table to make sure it is there. Once restarting the mysql daemon I tried logging in with the new root password that I just set and still get Access de...