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How to use Class in Java?
... behind the scenes over at this question , so we all know that Vector<int[]> is a vector of integer arrays, and HashTable<String, Person> is a table of whose keys are strings and values Person s.
However, what stumps me is the usage of Class<> .
...
MySQL DISTINCT on a GROUP_CONCAT()
...e string are duplicated).
What we need to do here is to split each string into different rows, and we first need to create a numbers table:
CREATE TABLE numbers (n INT);
INSERT INTO numbers VALUES
(1),(2),(3),(4),(5),(6),(7),(8),(9),(10);
then we can run this query:
SELECT
SUBSTRING_INDEX(
...
Method to Add new or update existing item in Dictionary
... in the framework - It is more tested and you are not the one who has to maintain the code
It is scalable: if you switch to multithreading your code is already prepared for it
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Escaping keyword-like column names in Postgres
...
Simply enclose year in double quotes to stop it being interpreted as a keyword:
INSERT INTO table (id, name, "year") VALUES ( ... );
From the documentation:
There is a second kind of identifier: the delimited identifier or
quoted identifier. It is formed by enclosing an...
What's the difference between `1L` and `1`?
...sume less memory. A double ("numeric") vector uses 8 bytes per element. An integer vector uses only 4 bytes per element. For large vectors, that's less wasted memory and less to wade through for the CPU (so it's typically faster).
Mostly this applies when working with indices.
Here's an example whe...
How to Use Order By for Multiple Columns in Laravel 4?
...
You can do as @rmobis has specified in his answer, [Adding something more into it]
Using order by twice:
MyTable::orderBy('coloumn1', 'DESC')
->orderBy('coloumn2', 'ASC')
->get();
and the second way to do it is,
Using raw order by:
MyTable::orderByRaw("coloumn1 DESC, coloumn2 AS...
How can I extract the folder path from file path in Python?
..._93_v141b.mdb')
>>> wkspFldr = existGDBPath.parent
>>> print wkspFldr
Path('T:\Data\DBDesign')
WITH OS MODULE
Use the os.path module:
>>> import os
>>> existGDBPath = r'T:\Data\DBDesign\DBDesign_93_v141b.mdb'
>>> wkspFldr = os.path.dirname(existGDBPat...
Reusing a PreparedStatement multiple times
...redStatement statement = connection.prepareStatement(SQL);
) {
int i = 0;
for (Entity entity : entities) {
statement.setObject(1, entity.getSomeProperty());
// ...
statement.addBatch();
i++;
if (i % 1000 == 0 || i == ...
Why do we always prefer using parameters in SQL statements?
... Injection attacks when the database is used in conjunction with a program interface such as a desktop program or web site.
In your example, a user can directly run SQL code on your database by crafting statements in txtSalary.
For example, if they were to write 0 OR 1=1, the executed SQL would be...
How do I set the request timeout for one controller action in an asp.net mvc application
... msdn.microsoft.com/en-us/library/vstudio/… executionTimeout Optional Int32 attribute. Specifies the maximum number of seconds that a request is allowed to execute before being automatically shut down by ASP.NET. This time-out applies only if the debug attribute in the compilation element is ...