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In MySQL queries, why use join instead of where?
...FROM clause
Write the association between the tables in the WHERE clause
SELECT *
FROM TABLE_A a,
TABLE_B b
WHERE a.id = b.id
Here's the query re-written using ANSI-92 JOIN syntax:
SELECT *
FROM TABLE_A a
JOIN TABLE_B b ON b.id = a.id
From a Performance Perspective:
Where su...
Limit file format when using ?
...te of <input type = "file"> can help to provide a filter in the file select dialog box of the OS. For example,
<!-- (IE 10+, Edge (EdgeHTML), Edge (Chromium), Chrome, Firefox 42+) -->
<input type="file" accept=".xls,.xlsx" />
should provide a way to filter out files other...
How do I execute a command and get the output of the command within C++ using POSIX?
...} /* switch (pid = fork())*/
}
You also might want to play around with select() and non-blocking reads.
fd_set readfds;
struct timeval timeout;
timeout.tv_sec = 0; /* Seconds */
timeout.tv_usec = 1000; /* Microseconds */
FD_ZERO(&readfds);
FD_SET(childToParent[READ_FD], &...
Sublime Text 2: Trim trailing white space on demand
...way that uses no plugins or settings and works in most situations.
Multi-Select and move cursor to the end of every line
Hold CTRL-Shift, Press Left, Right
The spaces and tabs at the end of the lines should now be selected. Press Delete or Backspace
Note - Special characters such as ( and + may ...
Easier way to debug a Windows service
...classes.
The solution I came up with uses the Environment.Interactive the select running mode, as suggested by other answers to this post.
static void Main()
{
ServiceBase[] servicesToRun;
servicesToRun = new ServiceBase[]
{
new MyService()
};
if (Environment.UserInter...
How to find server name of SQL Server Management Studio
...
Run this Query to get the name
SELECT @@SERVERNAME
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How to get all columns' names for all the tables in MySQL?
...
select * from information_schema.columns
where table_schema = 'your_db'
order by table_name,ordinal_position
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impro...
Event binding on dynamically created elements?
I have a bit of code where I am looping through all the select boxes on a page and binding a .hover event to them to do a bit of twiddling with their width on mouse on/off .
...
COALESCE Function in TSQL
...ks perfectly & gives a good visual explanation of how COALESCE works:
SELECT Name, Class, Color, ProductNumber,
COALESCE(Class, Color, ProductNumber) AS FirstNotNull
FROM Production.Product
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A weighted version of random.choice
...dom.choice (each element in the list has a different probability for being selected). This is what I came up with:
25 Answ...