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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...
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...
What's the better (cleaner) way to ignore output in PowerShell? [closed]
...est 1
(Measure-Command {
for ($i = 1; $i -lt 99; $i++)
{
$GetProcess | Select-Object -Property ProcessName | Out-Null
}
}).TotalMilliseconds
# Batch 2 - Test 2
(Measure-Command {
for ($i = 1; $i -lt 99; $i++)
{
[void]($GetProcess | Select-Object -Property ProcessName )
}
}).TotalMillise...
How can I join multiple SQL tables using the IDs?
...
You want something more like this:
SELECT TableA.*, TableB.*, TableC.*, TableD.*
FROM TableA
JOIN TableB
ON TableB.aID = TableA.aID
JOIN TableC
ON TableC.cID = TableB.cID
JOIN TableD
ON TableD.dID = TableA.dID
WHERE DATE(Tab...
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...
Local and global temporary tables in SQL Server
...varchar(150)
)
GO
insert into #LocalTemp values ( 1, 'Name','Address');
GO
Select * from #LocalTemp
The scope of Local temp table exist to the current session of current
user means to the current query window. If you will close the current
query window or open a new query window and will tr...
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...
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...
Find out what process registered a global hotkey? (Windows API)
...sual Studio\2017\Community\Common7\Tools\spyxx_amd64.exe)
In the menu bar, select Spy -> Log messages... (or hit Ctrl + M)
Check All Windows in System in the Additional Windows frame
Switch to the Messages tab
Click the Clear All button
Select WM_HOTKEY in the listbox, or check Keyboard in Messag...
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 ...