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sqlalchemy unique across multiple columns
... that represents locations. Locations "belong" to customers. Locations are identified by a unicode 10 character code. The "location code" should be unique among the locations for a specific customer.
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Foreign key constraint may cause cycles or multiple cascade paths?
...lter your design (or doing so would compromise things) then you should consider using triggers as a last resort.
FWIW resolving cascade paths is a complex problem. Other SQL products will simply ignore the problem and allow you to create cycles, in which case it will be a race to see which will ove...
The object 'DF__*' is dependent on column '*' - Changing int to double
...se DB migrations of my framework (Laravel) and dropColumn there? I have no idea how to drop the constraint which has mysterious name, autogenerated by SQL server :(
– JustAMartin
Feb 15 '16 at 16:00
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SQL update from one Table to another based on a ID match
... Sales_Import SI
INNER JOIN
RetrieveAccountNumber RAN
ON
SI.LeadID = RAN.LeadID;
MySQL and MariaDB
UPDATE
Sales_Import SI,
RetrieveAccountNumber RAN
SET
SI.AccountNumber = RAN.AccountNumber
WHERE
SI.LeadID = RAN.LeadID;
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How to return an empty ActiveRecord relation?
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A more portable solution that doesn't require an "id" column and doesn't assume there won't be a row with an id of 0:
scope :none, where("1 = 0")
I'm still looking for a more "correct" way.
share
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Set Value of Input Using Javascript Function
... currently using a YUI gadget. I also do have a Javascript function to validate the output that comes from the div that YUI draws for me:
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How to find a hash key containing a matching value
...te a multi-line script) to obtain the key given I want to match the client_id? E.g. How to get the key for client_id == "2180" ?
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LEFT OUTER JOIN in LINQ
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If a database driven LINQ provider is used, a significantly more readable left outer join can be written as such:
from maintable in Repo.T_Whatever
from xxx in Repo.T_ANY_TABLE.Where(join condition).DefaultIfEmpty()
If you omit the DefaultIfEmpty() yo...
Can Flask have optional URL parameters?
...
Another way is to write
@user.route('/<user_id>', defaults={'username': None})
@user.route('/<user_id>/<username>')
def show(user_id, username):
pass
But I guess that you want to write a single route and mark username as optional? If that's the ca...
Setting background colour of Android layout element
I am trying to, somewhat clone the design of an activity from a set of slides on Android UI design . However I am having a problem with a very simple task.
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