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SQL Add foreign key to existing column
...sed an error trying to create the relationships to the other table. Thanks all.
– ExceptionLimeCat
Apr 30 '12 at 20:35
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Is there a way to pass optional parameters to a function?
Is there a way in Python to pass optional parameters to a function while calling it and in the function definition have some code based on "only if the optional parameter is passed"
...
Understanding scala enumerations
...er Value representing the individual elements of the enumeration (it's actually an inner class, but the difference doesn't matter here).
Thus object WeekDay inherits that type member. The line type WeekDay = Value is just a type alias. It is useful, because after you import it elsewhere with import...
List of special characters for SQL LIKE clause
What is the complete list of all special characters for a SQL (I'm interested in SQL Server but other's would be good too) LIKE clause?
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Django set default form values
...ch is explained here
You have two options either populate the value when calling form constructor:
form = JournalForm(initial={'tank': 123})
or set the value in the form definition:
tank = forms.IntegerField(widget=forms.HiddenInput(), initial=123)
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MongoDB/NoSQL: Keeping Document Change History
... changes to one or more specific entities in a database. I've heard this called row versioning, a log table or a history table (I'm sure there are other names for it). There are a number of ways to approach it in an RDBMS--you can write all changes from all source tables to a single table (more of...
MongoDB Many-to-Many Association
... user document:
{name:"Joe"
,roles:["Admin","User","Engineer"]
}
To get all the Engineers, use:
db.things.find( { roles : "Engineer" } );
If you want to maintain the roles in separate documents then you can include the document's _id in the roles array instead of the name:
{name:"Joe"
,roles:...
How to remove array element in mongodb?
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Is there call back with this?
– Oliver Dixon
Sep 1 '15 at 17:34
1
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Swift Programming: getter/setter in stored property
...the new value that you assign will replace the one that was just set.
So all you have to do is this:
var rank: Int = 0 {
didSet {
// Say 1000 is not good for you and 999 is the maximum you want to be stored there
if rank >= 1000 {
rank = 999
}
}
}
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Submitting a multidimensional array via POST with php
...u would read the previous input name after cloning, and increment by 1 manually for each input name attribute in the clone.
– Daniel
Nov 18 '18 at 0:04
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