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Primary key/foreign Key naming convention [closed]
...e the USING syntax in SQL to save some typing and some boilerplate noise:
SELECT name, address, amount
FROM employees JOIN payroll USING (employee_id)
Another argument in favor of convention #2 is that it's the way the relational model was designed.
The significance of each column is
part...
Best way to give a variable a default value (simulate Perl ||, ||= )
...
return true;
} else {
return false;
}
}
function select_defined(){
$l = func_num_args();
$a = func_get_args();
for ($i=0; $i<$l; $i++){
if ($a[$i]) return $a[$i];
}
}
Examples:
// $foo ||= $bar;
set_unless_defined($foo, $bar);
//$foo = $baz ||...
How do I remove version tracking from a project cloned from git?
...efer to this article for a visual guide
In the view menu on the toolbar, select Options
In the Advanced Settings section, find Hidden files and Folders under the Files and Folders list and select Show hidden files and folders
Close the options menu and you should see all hidden folders and files ...
XPath with multiple conditions
What XPath can I use to select any category with a name attribute specified and any child node author with the value specified.
...
Maven Install on Mac OS X
...t:~$ sudo port install maven3 will Install Maven 3.0
you@host:~$ sudo port select --set maven maven3 selects that version of Maven
Installing by hand:
Download Maven from its homepage
Follow the installation instructions:
Extract the distribution archive, i.e.apache-maven-3.3.9-bin.tar.gz to th...
How can I restore the MySQL root user’s full privileges?
...Then execute this query:
insert into `user` (`Host`, `User`, `Password`, `Select_priv`, `Insert_priv`, `Update_priv`, `Delete_priv`, `Create_priv`, `Drop_priv`, `Reload_priv`, `Shutdown_priv`, `Process_priv`, `File_priv`, `Grant_priv`, `References_priv`, `Index_priv`, `Alter_priv`, `Show_db_priv`, ...
Can't Find Theme.AppCompat.Light for New Android ActionBar Support
... You get the styles.xml when you create the project with wizard select full screen app and hide controls
– JJ_Coder4Hire
Apr 16 '14 at 20:16
8
...
How To Capture A Minidump: Let Me Count The Ways - C/C++ - 清泛网 - 专注C/C++及内核技术
... in the Applications or the Processes tabs, right click on the process and select Create Dump File.
After the minidump is finished, you’ll see the dialog showing you where the dump was created. A nice hidden treat is that the path shown is a read only edit control you can select and copy so...
Which rows are returned when using LIMIT with OFFSET in MySQL?
...
OFFSET is nothing but a keyword to indicate starting cursor in table
SELECT column FROM table LIMIT 18 OFFSET 8 -- fetch 18 records, begin with record 9 (OFFSET 8)
you would get the same result form
SELECT column FROM table LIMIT 8, 18
visual representation (R is one record in the table i...
Qt events and signal/slots
...lated?
An idle main loop (Qt’s for example) is usually “stuck” in a select() call of the operating system. That call makes the application “sleep”, while it passes a bunch of sockets or files or whatever to the kernel asking for: if something changes on these, let the select() call return...