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How to add a primary key to a MySQL table?
...mn, you can always add the primary key:
ALTER TABLE goods ADD PRIMARY KEY(id)
As to why your script wasn't working, you need to specify PRIMARY KEY, not just the word PRIMARY:
alter table goods add column `id` int(10) unsigned primary KEY AUTO_INCREMENT;
...
Why am I getting a “401 Unauthorized” error in Maven?
...line it works, but then when you do it from a script it fails (because it didn't exist in the repository the first time around). Either publish using a different version number, or delete the old artefact on the server and republish.
The SNAPSHOTS repository (as opposed to the releases repository)...
CSS styling in Django forms
...e'> in Django
class MyForm(forms.Form):
myfield = forms.CharField(widget=forms.TextInput(attrs={'class' : 'myfieldclass'}))
or
class MyForm(forms.ModelForm):
class Meta:
model = MyModel
def __init__(self, *args, **kwargs):
super(MyForm, self).__init__(*args, **kwa...
Sequence contains no elements?
...point on that line, or a Debug.Print before it, in both cases and see what ID contains.
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INSERT IF NOT EXISTS ELSE UPDATE?
...ang_conflict.html.
You want something like:
insert or replace into Book (ID, Name, TypeID, Level, Seen) values
((select ID from Book where Name = "SearchName"), "SearchName", ...);
Note that any field not in the insert list will be set to NULL if the row already exists in the table. This is why ...
.Contains() on a list of custom class objects
...
You need to implement IEquatable or override Equals() and GetHashCode()
For example:
public class CartProduct : IEquatable<CartProduct>
{
public Int32 ID;
public String Name;
public Int32 Number;
public Decimal CurrentPrice;
public CartP...
Using async/await for multiple tasks
...
int[] ids = new[] { 1, 2, 3, 4, 5 };
Parallel.ForEach(ids, i => DoSomething(1, i, blogClient).Wait());
Although you run the operations in parallel with the above code, this code blocks each thread that each operation runs on. ...
Rails auto-assigning id that already exists
...
Rails is probably using the built-in PostgreSQL sequence. The idea of a sequence is that it is only used once.
The simplest solution is to set the sequence for your company.id column to the highest value in the table with a query like this:
SELECT setval('company_id_seq', (SELECT max(...
Android: Test Push Notification online (Google Cloud Messaging) [closed]
...
Found a very easy way to do this.
Open http://phpfiddle.org/
Paste following php script in box. In php script set API_ACCESS_KEY, set device ids separated by coma.
Press F9 or click Run.
Have fun ;)
<?php
// API access key from Google API's Console
define( 'API_ACCE...