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Check if a temporary table exists and delete if it exists before creating a temporary table
I am using the following code to check if the temporary table exists and drop the table if it exists before creating again. It works fine as long as I don't change the columns. If I add a column later, it will give an error saying "invalid column". Please let me know what I am doing wrong.
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mysqli or PDO - what are the pros and cons? [closed]
...ry("SELECT * FROM students");
/* MAGIC HAPPENS HERE */
$stmt->setFetchMode(PDO::FETCH_INTO, new Student);
foreach($stmt as $student)
{
echo $student->getFullName().'<br />';
}
$dbh = null;
}
catch(PDOException $e)
{
echo $e->getMessage();
}
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How is Python's List Implemented?
Is it a linked list, an array? I searched around and only found people guessing. My C knowledge isn't good enough to look at the source code.
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C pointer to array/array of pointers disambiguation
What is the difference between the following declarations:
13 Answers
13
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SQL how to increase or decrease one for a int column in one command
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To answer the first:
UPDATE Orders SET Quantity = Quantity + 1 WHERE ...
To answer the second:
There are several ways to do this. Since you did not specify a database, I will assume MySQL.
INSERT INTO table SET x=1, y=2 ON DUPLICATE KEY UPDATE x=x+1, y=y...
Else clause on Python while statement
I've noticed the following code is legal in Python. My question is why? Is there a specific reason?
12 Answers
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Ways to iterate over a list in Java
...gs).
EDIT: As @iX3 points out in a comment, you can use a ListIterator to set the current element of a list as you are iterating. You would need to use List#listIterator() instead of List#iterator() to initialize the loop variable (which, obviously, would have to be declared a ListIterator rather t...
GROUP BY with MAX(DATE) [duplicate]
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You cannot include non-aggregated columns in your result set which are not grouped. If a train has only one destination, then just add the destination column to your group by clause, otherwise you need to rethink your query.
Try:
SELECT t.Train, t.Dest, r.MaxTime
FROM (
SEL...
run main class of Maven project [duplicate]
...a way that the main class (which doesn't require any arguments) can be run from the command-line using a maven command like:
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How to access a preexisting collection with Mongoose?
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