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Difference between clustered and nonclustered index [duplicate]
...a completely different object within the table that contains the column(s) selected for indexing and a pointer back to the table’s rows containing the data. It is like an index in the last pages of a book, where keywords are sorted and contain the page number to the material of the book for faster...
How can I prevent SQL injection in PHP?
...
Using PDO (for any supported database driver):
$stmt = $pdo->prepare('SELECT * FROM employees WHERE name = :name');
$stmt->execute([ 'name' => $name ]);
foreach ($stmt as $row) {
// Do something with $row
}
Using MySQLi (for MySQL):
$stmt = $dbConnection->prepare('SELECT * FROM...
compilation warning: no rule to process file for architecture i386
...w:-
Some .md, .mdown .h files are included in the Compile Sources
Step 1) Select Project Navigator
Step 2) Select your project
Step 3) Select your targetStep
Step 4) Select Build PhasesStep
Step 5) Move files which we don't want the compiler to process from Compile Sources to Copy Bundle Resource...
How to use android emulator for testing bluetooth application?
... virtual machine set the network adapter to 'Bridged'. ·
Start the VM and select 'Live CD VESA' at boot.
Now you need to find out the IP of this VM. Go to terminal in VM (use Alt+F1
& Alt+F7 to toggle) and use the netcfg command to find this.
Now you need open a command prompt and go to your ...
Stop Excel from automatically converting certain text values to dates
...qualifier if you have surrounded your values by quotes
In the third page, select every column individually and assign each the type "Text" instead of "General" to stop Excel from messing with your data.
Hope this helps you or someone with a similar problem!
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MySQL/SQL: Group by date only on a Datetime column
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Cast the datetime to a date, then GROUP BY using this syntax:
SELECT SUM(foo), DATE(mydate) FROM a_table GROUP BY DATE(a_table.mydate);
Or you can GROUP BY the alias as @orlandu63 suggested:
SELECT SUM(foo), DATE(mydate) DateOnly FROM a_table GROUP BY DateOnly;
Though I don't think...
How to show SQL queries run in the Rails console?
...ecord::Relation’s to_sql method:
User.where(:id => 3).to_sql
#=> "SELECT \"users\".* FROM \"users\" WHERE \"users\".\"id\" = 3"
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Random row selection in Pandas dataframe
Is there a way to select random rows from a DataFrame in Pandas.
6 Answers
6
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Selecting last element in JavaScript array [duplicate]
...gth less 1.
Mozilla Docs on Slice
Performance of the various methods for selecting last array element
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INNER JOIN vs LEFT JOIN performance in SQL Server
...(ID, Name) VALUES (4, 'Four')
INSERT #Test2 (ID, Name) VALUES (5, 'Five')
SELECT *
FROM #Test1 t1
INNER JOIN #Test2 t2
ON t2.Name = t1.Name
SELECT *
FROM #Test1 t1
LEFT JOIN #Test2 t2
ON t2.Name = t1.Name
DROP TABLE #Test1
DROP TABLE #Test2
If you run this and view the execution plan, you'll se...