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How many database indexes is too many?
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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...
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...
How do I connect to a MySQL Database in Python?
...ueries you need
cur = db.cursor()
# Use all the SQL you like
cur.execute("SELECT * FROM YOUR_TABLE_NAME")
# print all the first cell of all the rows
for row in cur.fetchall():
print row[0]
db.close()
Of course, there are thousand of possibilities and options; this is a very basic example. Y...
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 to find Unused Amazon EC2 Security groups
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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...
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...
C++实现一款简单完整的聊天室服务器+客户端 - C/C++ - 清泛网 - 专注C/C++及内核技术
C++实现一款简单完整的聊天室服务器+客户端Linux下select函数实现的聊天服务器消息缓冲区类MessageBuffer，接收线程将受到的消息放入缓冲区，发送线程从缓冲区中取出消息MessageBuffe...目录：
Linux下select函数实现的聊天服务器
基...
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 ...
Targeting .NET Framework 4.5 via Visual Studio 2010
...r (Build -> Configuration Manager) make sure the ".NET 4.5" platform is selected for your project.
Still in the configuration manager, create a new solution platform for ".NET 4.5" (you can base it off "Any CPU") and make sure ".NET 4.5" is selected for the solution.
Build your project and check ...
Using LINQ to concatenate strings
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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...