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A migration to add unique constraint to a combination of columns
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The problem with the model level validation is that it doesn't scale. Two servers could run the same data through at the same time (like a double tap on an api heavy app) I have two identical records in my DB right now and the model has the validation..
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SQL WHERE condition is not equal to?
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You can do like this
DELETE FROM table WHERE id NOT IN ( 2 )
OR
DELETE FROM table WHERE id <> 2
As @Frank Schmitt noted, you might want to be careful about the NULL values too. If you want to delete everything which is not 2(including the NULLs) then add O...
Aligning textviews on the left and right edges in Android layout
I am getting started with Android. I am having trouble getting a simple layout going.
9 Answers
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WiX tricks and tips
...ion. For example, if a user sets custom install directory.
<Property Id="INSTALLLOCATION">
<RegistrySearch Id="RegistrySearch" Type="raw" Root="HKLM" Win64="$(var.Win64)"
Key="Software\Company\Product" Name="InstallLocation" />
</Property>
Note: WiX guru Rob...
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;
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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 ...
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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