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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
...
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...
Drop all tables whose names begin with a certain string
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MYSQL: SELECT concat('DROP TABLE ',TABLE_NAME,";") as data FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_NAME LIKE '[prefix]%' --- for those who like me found this thread
– Andre
Nov 6 '12...
How to add directory to classpath in an application run profile in IntelliJ IDEA?
...
@uaaquarius, Why is it that if I add mysql-connector-java-5.1.45/mysql-connector-java-5.1.45-bin.jar as dependency using the other method at stackoverflow.com/a/16742141/632951 it works, but doing using -Xbootclasspath/a it doesn't?
– Pace...
How to enable PHP short tags?
...
/etc/php.d/gd.ini,
/etc/php.d/json.ini,
/etc/php.d/mcrypt.ini,
/etc/php.d/mysql.ini,
/etc/php.d/mysqli.ini,
/etc/php.d/pdo.ini,
/etc/php.d/pdo_mysql.ini,
/etc/php.d/pdo_sqlite.ini,
/etc/php.d/phar.ini,
/etc/php.d/sqlite3.ini,
/etc/php.d/zip.ini
See 2nd line from the comment output.The file will b...
Select top 10 records for each category
...d
HAVING COUNT(*) <= 10;
update: This example of GROUP BY works in MySQL and SQLite only, because those databases are more permissive than standard SQL regarding GROUP BY. Most SQL implementations require that all columns in the select-list that aren't part of an aggregate expression are al...
PreparedStatement with list of parameters in a IN clause [duplicate]
...unds great, but i get an java.sql.SQLFeatureNotSupportedException from the mysql driver 5.1.39
– benez
Aug 31 '16 at 13:53
4
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How to select all records from one table that do not exist in another table?
...E b.Key IS NULL;
https://www.cloudways.com/blog/how-to-join-two-tables-mysql/
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ActiveRecord.find(array_of_ids), preserving order
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The answer is for mysql only
There is a function in mysql called FIELD()
Here is how you could use it in .find():
>> ids = [100, 1, 6]
=> [100, 1, 6]
>> WordDocument.find(ids).collect(&:id)
=> [1, 6, 100]
>> WordD...