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SQL UPDATE all values in a field with appended string CONCAT not working
...
That's pretty much all you need:
mysql> select * from t;
+------+-------+
| id | data |
+------+-------+
| 1 | max |
| 2 | linda |
| 3 | sam |
| 4 | henry |
+------+-------+
4 rows in set (0.02 sec)
mysql> update t set data=concat(d...
How to define two fields “unique” as couple
... How would you handle this say if volume_number could be null? Mysql won't seem to enforce unique in that case.
– Greg
Jun 27 '11 at 17:28
27
...
Laravel Schema onDelete set null
...cument what options there are, but I think you can assume it's the default mysql values (see ../ vendor / laravel / framework / src / Illuminate / Database / Schema / Grammars / Grammar.php)
– Dirk Jan
Mar 23 at 14:47
...
How to make Sequelize use singular table names
...ames
freezeTableName: true
}
}
var sequelize = new Sequelize('mysql://root:123abc@localhost:3306/mydatabase', opts)
Now when you define your entities, you don't have to specify freezeTableName: true:
var Project = sequelize.define('Project', {
title: Sequelize.STRING,
descrip...
Auto reloading python Flask app upon code changes
...ue
virtualenv = /Users/xxxx/.virtualenvs/sites_env
chdir = /Users/xxx/site_root
module = site_module:register_debug_server()
callable = app
uid = myuser
chmod-socket = 660
log-date = true
workers = 1
py-autoreload = 1
site_root/__init__.py
def register_debug_server():
from werkzeug.debug impo...
Android View.getDrawingCache returns null, only null
...
View root = currActivity.getWindow().getDecorView().findViewById(android.R.id.content); root.setDrawingCacheEnabled(true); root.layout(0, 0, 480, 854); mBitmap = root.getDrawingCache();
...
Cannot change column used in a foreign key constraint
... DELETE ) will wait till timeout or UNLOCK TABLES; is executed
http://dev.mysql.com/doc/refman/5.5/en/lock-tables.html
EDIT 2: OP asked for a more detailed explanation of the line "The type and definition of foreign key field and reference must be equal. This means your foreign key disallows chang...
B-Tree vs Hash Table
In MySQL, an index type is a b-tree, and access an element in a b-tree is in logarithmic amortized time O(log(n)) .
5 Answ...
How to disable back swipe gesture in UINavigationController on iOS 7
...etting the delegate to nil leads to hanging issues when you go back to the root view controller and make a swipe gesture before navigating elsewhere.
The following example assumes iOS 7:
{
id savedGestureRecognizerDelegate;
}
- (void)viewWillAppear:(BOOL)animated
{
savedGestureRecognizer...
How to perform file system scanning
...tf("Visited: %s\n", path)
return nil
}
func main() {
flag.Parse()
root := flag.Arg(0)
err := filepath.Walk(root, visit)
fmt.Printf("filepath.Walk() returned %v\n", err)
}
Please note that filepath.Walk walks the directory tree recursively.
This is an example run:
$ mkdir -p dir1/dir...