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Finding duplicate values in a SQL table
...QL Server 2017) still requires all non-aggregated columns in the GROUP BY.
MySQL is unpredictable and you need sql_mode=only_full_group_by:
GROUP BY lname ORDER BY showing wrong results;
Which is the least expensive aggregate function in the absence of ANY() (see comments in accepted answer).
Ora...
How do you write multiline strings in Go?
...DanieleD That's a slight nonsequitur, but which dialect? Presumably mainly MySQL? stackoverflow.com/a/10574031 Note that by extension of the same argument, it's a pain for embedding markdown, or shell scripts (if you opt to use backtick in place of $(abcd)).
– Ivan Vučica
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Add a reference column migration in Rails 4
... Active Record only supports single column foreign keys and currently only mysql, mysql2 and PostgreSQL adapters are supported. Don't try this with other adapters like sqlite3, etc. Refer to Rails Guides: Foreign Keys for your reference.
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How can I detect if the user is on localhost in PHP?
...n.
I think what you remember with PHPMyAdmin is something different: Many MySQL Servers are configured so that they can only be accessed from localhost for security reasons.
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How to use count and group by at the same select statement
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needs alias otherwise wouldnt work in mysql. select count(*) from( ) agr
– amas
Jan 9 '14 at 6:54
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Why are joins bad when considering scalability?
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...except in MySQL, which seems to have performance problems with large numbers of joins regardless of how your indexes look. Or at least it has in the past.
– Powerlord
Apr 12 '10 at 17:53
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ORA-00979 not a group by expression
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@AaronDigulla That's what MySQL does, and the world didn't end :p
– Chris Baker
Aug 27 '14 at 21:32
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Add primary key to existing table
...primary key for sql table.
First, you have to drop your old primary key.
MySQL:
ALTER TABLE Persion
DROP PRIMARY KEY;
SQL Server / Oracle / MS Access:
ALTER TABLE Persion
DROP CONSTRAINT 'constraint name';
You have to find the constraint name in your table. If you had
given constraint n...
Call to undefined method mysqli_stmt::get_result
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Please read the user notes for this method:
http://php.net/manual/en/mysqli-stmt.get-result.php
It requires the mysqlnd driver... if it isn't installed on your webspace you will have to work with BIND_RESULT & FETCH!
https://secure.php.net/manual/en/mysqli-stmt.bind-result.php
https://s...
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...