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How to install both Python 2.x and Python 3.x in Windows
...ed Python 2.7.6.
How to...
Start > in the search type in environment select "Edit environment variables to your account"1
Scroll down to Path, select path, click edit.
Add C:\Python27;
so you should have paths to both versions of Python there, but if you don't this you can easily edit it so th...
Correct way to pass multiple values for same parameter name in GET request
...s handle forms by default. For example take a look at the form element <select multiple> and how it handles multiple values from this example at w3schools.
<form action="/action_page.php">
<select name="cars" multiple>
<option value="volvo">Volvo</option>
<optio...
How many database indexes is too many?
...
It depends on the operations that occur on the table.
If there's lots of SELECTs and very few changes, index all you like.... these will (potentially) speed the SELECT statements up.
If the table is heavily hit by UPDATEs, INSERTs + DELETEs ... these will be very slow with lots of indexes since t...
SQL - Update multiple records in one query
...the rows u need using a small script.
UPDATE [Table]
SET couloumn1= (select couloumn1 FROM Table WHERE IDCouloumn = [PArent ID]),
couloumn2= (select couloumn2 FROM Table WHERE IDCouloumn = [PArent ID]),
couloumn3= (select couloumn3 FROM Table WHERE IDCouloumn = [PArent ID]),
cou...
How do you move a file?
...files, right-dragged, the regular windows explorer menu came up. It let me select "move" but it wasn't an SVN option so I'm not sure anything even happened. When I checked to see if there were modifications, it said 300 files were deleted and 300 were non-versioned. This doesn't seem like it worked ...
How to find Unused Amazon EC2 Security groups
...
If you select all of your security groups in the EC2 console, then press actions -> Delete Security Groups, a popup will appear telling you that you cannot delete security groups that are attached to instances, other security gro...
Why is there no logical xor in JavaScript?
...
JavaScript traces its ancestry back to C, and C does not have a logical XOR operator. Mainly because it's not useful. Bitwise XOR is extremely useful, but in all my years of programming I have never needed a logical XOR.
If you have two boolean variables you can mim...
Using LINQ to concatenate strings
...
Real example from my code:
return selected.Select(query => query.Name).Aggregate((a, b) => a + ", " + b);
A query is an object that has a Name property which is a string, and I want the names of all the queries on the selected list, separated by comma...
Getting raw SQL query string from PDO prepared statements
...the principle is the same.
081016 16:51:28 2 Query prepare s1 from 'select * from foo where i = ?'
2 Prepare [2] select * from foo where i = ?
081016 16:51:39 2 Query set @a =1
081016 16:51:47 2 Query execute s1 using @a
2 Execute [2] select...
NullPointerException in Java with no StackTrace
...interException) occurs for the first time, the full stack trace is printed and the JVM remembers the stack trace (or maybe just the location of the code). When that exception occurs often enough, the stack trace is not printed anymore, both to achieve better performance and not to flood the log with...