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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...
How can I efficiently select a Standard Library container in C++11?
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Where can I locate themes for VS2012
... in another machine and at first it did not work. It turned out that I had selected the key name from this response by double clicking it, then copied it, then pasted it in regedit. Well, by doing so I had inadvertently created the key with a trailing space in the name! And hence it did not work.
S...
How do I get a substring of a string in Python?
...is a step. So reversing a string is as simple as:
some_string[::-1]
Or selecting alternate characters would be:
"H-e-l-l-o- -W-o-r-l-d"[::2] # outputs "Hello World"
The ability to step forwards and backwards through the string maintains consistency with being able to array slice from the star...
Where is SQL Server Management Studio 2012?
...all the entire SQL Server package, later on in the install process you can select to only install SSMS.
– Baodad
Jul 24 '13 at 18:21
...
How do I execute a string containing Python code in Python?
...ting code should generally be the position of last resort: It's slow, ugly and dangerous if it can contain user-entered code. You should always look at alternatives first, such as higher order functions, to see if these can better meet your needs.
...
Differences between INDEX, PRIMARY, UNIQUE, FULLTEXT in MySQL?
...e - which are typically implemented internally using b-trees (allowing for selecting, sorting or ranges starting from left most column) or hash tables (allowing for selection starting from left most column).
Where the other index types are general-purpose, a FULLTEXT index is specialised, in that it...
What is non-blocking or asynchronous I/O in Node.js?
...rage is a blocking operation as it stalls execution to read. On the other hand, fetch is a non-blocking operation as it does not stall alert(3) from execution.
// Blocking: 1,... 2
alert(1);
var value = localStorage.getItem('foo');
alert(2);
// Non-blocking: 1, 3,... 2
alert(1);
fetch('example.com...
How to get the IP address of the docker host from inside a docker container
... title says. I need to be able to retrieve the IP address the docker hosts and the portmaps from the host to the container, and doing that inside of the container.
...
Determine if running on a rooted device
...e root is available. Rather than having this feature fail when it is used (and then show an appropriate error message to the user), I'd prefer an ability to silently check if root is available first, and if not,hide the respective options in the first place.
...