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In PHP, how do you change the key of an array element?
...y, you can change the key directly from the mysql statement:
instead of
"select ´id´ from ´tablename´..."
use something like:
"select ´id´ **as NEWNAME** from ´tablename´..."
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i...
When do we have to use copy constructors?
...structor with a correct signature and commit the sin of turning to a const_cast.
Copy-on-write (COW)
A COW container that has given away direct references to its internal data MUST be deep-copied at the time of construction, otherwise it may behave as a reference counting handle.
Though COW ...
Differences and relationship between glActiveTexture and glBindTexture
...rent objects, and all of our object manipulation functions are adjusted to select from the current object.
When you change the currently active object, you change the entire set of target locations. So you can bind something that goes into current object 0, switch to current object 4, and will be m...
How can I exclude one word with grep?
...
-v or --invert-match select non-matching lines. In your case grep -v 'unwanted_word' file or grep --invert-match 'unwanted_word' file.
– adamski.pro
Nov 29 '16 at 7:10
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Execute raw SQL using Doctrine 2
...public function getAuthoritativeSportsRecords()
{
$sql = "
SELECT name,
event_type,
sport_type,
level
FROM vnn_sport
";
$em = $this->getDoctrine()->getManager();
$stmt = $em->getConnection()->prepare($sql...
How to select the row with the maximum value in each group
In a dataset with multiple observations for each subject I want to take a subset with only the maximum data value for each record. For example, with a following dataset:
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Postgres NOT in array
...
SELECT COUNT(*) FROM "messages" WHERE NOT (3 = ANY (recipient_ids))
You can always negate WHERE (condition) with WHERE NOT (condition)
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When do I need to use Begin / End Blocks and the Go keyword in SQL Server?
..., and IF statements, etc, where you need more then one step...
IF EXISTS (SELECT * FROM my_table WHERE id = @id)
BEGIN
INSERT INTO Log SELECT @id, 'deleted'
DELETE my_table WHERE id = @id
END
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What is the difference between Non-Repeatable Read and Phantom Read?
...e query have the same value before and after, but different rows are being selected (because B has deleted or inserted some). Example: select sum(x) from table; will return a different result even if none of the affected rows themselves have been updated, if rows have been added or deleted.
In ...
Convert an image (selected by path) to base64 string
How do you convert an image from a path on the user's computer to a base64 string in C#?
12 Answers
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