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Getting “Lock wait timeout exceeded; try restarting transaction” even though I'm not using a transac
...heck your database transaction isolation level in the mysql cli:
mysql> SELECT @@GLOBAL.tx_isolation, @@tx_isolation, @@session.tx_isolation;
+-----------------------+-----------------+------------------------+
| @@GLOBAL.tx_isolation | @@tx_isolation | @@session.tx_isolation |
+----------------...
Are database triggers evil? [closed]
...lumns wouldn't exist and you'd have to process a function on each row when selecting them. That's likely to kill DBMS performance, far better to create the auto-generated column at insert/update time since that's the only time it changes.
Also, lack of triggers would prevent data rules from being e...
How can I backup a remote SQL Server database to a local drive?
...er to perform a decent backup of your database, even on a remote server:
Select the database you wish to backup and hit next,
In the options it presents to you:
In 2010: under the Table/View Options, change 'Script Data' and 'Script Indexes' to True and hit next,
In 2012: under 'General', change...
How can I prevent SQL injection in PHP?
...
Using PDO (for any supported database driver):
$stmt = $pdo->prepare('SELECT * FROM employees WHERE name = :name');
$stmt->execute([ 'name' => $name ]);
foreach ($stmt as $row) {
// Do something with $row
}
Using MySQLi (for MySQL):
$stmt = $dbConnection->prepare('SELECT * FROM...
How to combine two or more querysets in a Django view?
...s. For example:
>>> qs1.union(qs2, qs3)
The UNION operator selects only distinct values by default. To allow duplicate values, use the all=True
argument.
union(), intersection(), and difference() return model instances of
the type of the first QuerySet even if the arguments ...
Intellij shortcut to convert code to upper or lower case?
... I have trouble where sometimes pressing CTRL+SHIFT+U just replaces the selected text with the letter U.... sometimes it works, but usually it just does the replacing.
– Trenton
Jul 31 '14 at 16:15
...
Apply multiple functions to multiple groupby columns
... group. When aggregating, g will be a Series. Passing g.index to df.ix[] selects the current group from df. I then test if column C is less than 0.5. The returned boolean series is passed to g[] which selects only those rows meeting the criteria.
In [95]: cust = lambda g: g[df.loc[g.index]['C']...
mongodb: insert if not exists
...what data you want to write:
data = {"$set":{"key2":"value2"}}
Now your selected document will update the value of "key2" only and leave everything else untouched.
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...
disable nganimate for some elements
...ng-show , etc, are affected by that, I want to leverage ngAnimate for some selected elements.
For performance and some bugs in elements that shows and hide very speedy.
...
How do I update a Linq to SQL dbml file?
... was getting 'Specified cast is not valid' errors when performing a simple select on a view. Including 1b fixed it for me
– tomfumb
Nov 29 '11 at 19:40
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