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What is boxing and unboxing and what are the trade offs?
...ect o = i;// Boxing
int j = (int)o;// UnBoxing
Value Types are: int, char and structures, enumerations.
Reference Types are:
Classes,interfaces,arrays,strings and objects
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MySQL DROP all tables, ignoring foreign keys
... these tweaks:
Limit the generated drops to your database like this:
SELECT concat('DROP TABLE IF EXISTS `', table_name, '`;')
FROM information_schema.tables
WHERE table_schema = 'MyDatabaseName';
Note 1: This does not execute the DROP statements, it just gives you a list of them. You will n...
MySQL vs MongoDB 1000 reads
...s://github.com/webcaetano/mongo-mysql
10 rows
mysql insert: 1702ms
mysql select: 11ms
mongo insert: 47ms
mongo select: 12ms
100 rows
mysql insert: 8171ms
mysql select: 10ms
mongo insert: 167ms
mongo select: 60ms
1000 rows
mysql insert: 94813ms (1.58 minutes)
mysql select: 13ms
mongo inser...
Convert INT to VARCHAR SQL
I am using Sybase and I am doing a select which returns me a column called "iftype", but its type is int and I need to convert into varchar. When I try to do the select without the convert function I get this error:
...
Run an app on a multiple devices automatically in Android Studio
...
if you shold shift, select all devices, and you click "Run on the same device next time", even if it doesn't' put plural "devices" it will automatically run on all the next time.
– OWADVL
Oct 28 '14 at 10:2...
Importing a GitHub project into Eclipse
...ries")
Eclipse with GitHub
EGit tutorial
Copy the URL from GitHub and select in Eclipse from the menu the
File → Import → Git → Projects from Git
If the Git repo isn't cloned yet:
In> order to checkout a remote project, you will have to clone its repository first.
Open the E...
How can I make an entire HTML form “readonly”?
...e="text" name="something" placeholder="enter some text" />
<select>
<option value="0" disabled="disabled" selected="selected">select somethihng</option>
<option value="1">woot</option>
<option value="2">is</opt...
Function vs. Stored Procedure in SQL Server
...-----------+----------------------------------------+
| We can't use SP in SELECT/ | We can use UDF in SELECT/ WHERE/ |
| WHERE/ HAVING statement. | HAVING statement. |
+---------------------------------+----------------------------------------+
| We can use ex...
Most efficient way to concatenate strings?
...gt; and other input types, with and without separators of different types (Char, String), but here I show the simple case of concatenating all strings in an array into a single string, with no separator. Latest version here is developed and unit-tested on C# 7 and .NET 4.7.
There are two keys to h...
LEFT JOIN only first row
...rtist_id) will be the earliest.
So try something like this (untested...)
SELECT *
FROM feeds f
LEFT JOIN artists a ON a.artist_id = (
SELECT
MIN(fa.artist_id) a_id
FROM feeds_artists fa
WHERE fa.feed_id = f.feed_id
) a
...