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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...
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 ...
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. ...
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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Rails auto-assigning id that already exists
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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(...
.Contains() on a list of custom class objects
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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...
Android: Test Push Notification online (Google Cloud Messaging) [closed]
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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...
Converting an array of objects to ActiveRecord::Relation
...jiSaini I’m unsure of the exact method you’re referring to, please provide doc or source link. Though, if it’s deprecated, not a very viable solution as it’ll likely go away soon.
– Andrew Marshall
Feb 14 '17 at 14:09
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