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selecting unique values from a column
I have a MySQL table which contains the following type of information:
9 Answers
9
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Add 2 hours to current time in MySQL?
Which is the valid syntax of this query in MySQL?
5 Answers
5
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How do I get the current date and time in PHP?
...tetime;
$now = new DateTime();
echo $now->format('Y-m-d H:i:s'); // MySQL datetime format
echo $now->getTimestamp(); // Unix Timestamp -- Since PHP 5.3
And to specify the timezone:
$now = new DateTime(null, new DateTimeZone('America/New_York'));
$now->setTimezone(new DateTi...
How to work with complex numbers in C?
...introduced in mathematics, from the need of calculating negative quadratic roots. Complex number concept was taken by a variety of engineering fields.
Today that complex numbers are widely used in advanced engineering domains such as physics, electronics, mechanics, astronomy, etc...
Real and imag...
MySQL INNER JOIN select only one row from second table
I have a users table and a payments table, for each user, those of which have payments, may have multiple associated payments in the payments table. I would like to select all users who have payments, but only select their latest payment. I'm trying this SQL but i've never tried nested SQL sta...
mysqli_fetch_assoc() expects parameter / Call to a member function bind_param() errors. How to get t
In my local/development environment, the MySQLi query is performing OK. However, when I upload it on my web host environment, I get this error:
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Master-master vs master-slave database architecture?
...uture. I came across
Master-Slave Replication
Master-Master Replication
MySQL Cluster
I have decided to settle for using MySQL Cluster for my use case. However please see below for the various pros and cons that I have compiled
1. Master-Slave Replication
Pros
Analytic applications can rea...
Explain Morris inorder tree traversal without using stacks or recursion
...works:
X
/ \
Y Z
/ \ / \
A B C D
First, X is the root, so it is initialized as current. X has a left child, so X is made the rightmost right child of X's left subtree -- the immediate predecessor to X in an inorder traversal. So X is made the right child of B, then current ...
Error pushing to GitHub - insufficient permission for adding an object to repository database
...new files created by another user to maintain the group permissions of the root directory. Otherwise, you'll have errors pushing up to the repository. See setuid and setgid
– syvex
Jul 7 '11 at 17:05
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To prevent a memory leak, the JDBC Driver has been forcibly unregistered
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Here mostly same but with additional MySQL/MariaDB handling code github.com/spring-projects/spring-boot/issues/2612
– gavenkoa
Dec 19 '15 at 9:59
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