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SQL Server: Is it possible to insert into two tables at the same time?
My database contains three tables called Object_Table , Data_Table and Link_Table . The link table just contains two columns, the identity of an object record and an identity of a data record.
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Rails: How do I create a default value for attributes in Rails activerecord's model? [duplicate]
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add_column :status, :string, :default => "P"
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OR
You can use a callback, before_save
class Task < ActiveRecord::Base
before_save :default_values
def default_values
self.status ||= 'P' # note self.status = 'P' if self.status.nil? might be safer (per @frontendbeauty)
end
end
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Pythonic way to check if a file exists? [duplicate]
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It seems to me that all other answers here (so far) fail to address the race-condition that occurs with their proposed solutions.
Any code where you first check for the files existence, and then, a few lines later in your program, you create it...
What's the function like sum() but for multiplication? product()?
...Older info: Python 3.7 and prior
The function you're looking for would be called prod() or product() but Python doesn't have that function. So, you need to write your own (which is easy).
Pronouncement on prod()
Yes, that's right. Guido rejected the idea for a built-in prod() function because he t...
HTTP Error 404.3 - Not Found" while browsing wcf service on Windows Server 2008(64bit)
...trol panel -> Turn Windows feature on or off -> and make sure you've all the options ticked as mentioned in below screenshot.
You might need to activate each box and accept in case you get errors when activating all features at once
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How to copy data from one table to another new table in MySQL?
...d,from_uid,now(),'Pending','Assigned'
FROM table1
If you want to include all rows from table1. Otherwise you can add a WHERE statement to the end if you want to add only a subset of table1.
I hope this helps.
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How to check if type of a variable is string?
...atter, because Python 3.x is not meant to be compatible with Python 2.x at all.
– netcoder
Jul 15 '13 at 17:45
2
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Using StringWriter for XML Serialization
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<TL;DR> The problem is rather simple, actually: you are not matching the declared encoding (in the XML declaration) with the datatype of the input parameter. If you manually added <?xml version="1.0" encoding="utf-8"?><test/> to the string, then declaring...
Why does base64 encoding require padding if the input length is not divisible by 3?
... the protocol used padding, there would be no need to transmit a length at all. The data could be encoded as it came in from the camera, each chunk terminated with padding, and the receiver would be able to decode the stream correctly.
Obviously that's a very contrived example, but perhaps it illus...
In Subversion can I be a user other than my login name?
...e/password again though. You need to login like the above once and you are all set for the subsequent times(Unless you restart your machine).
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