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python pandas dataframe to dictionary
I've a two columns dataframe, and intend to convert it to python dictionary - the first column will be the key and the second will be the value. Thank you in advance.
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Rails :include vs. :joins
... that requires it. In some cases, you know the join will be more efficient and will not incur the risk of duplication.
– Jonathan Swartz
Nov 21 '13 at 0:28
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How to implement the activity stream in a social network
I'm developing my own social network, and I haven't found on the web examples of implementation the stream of users' actions... For example, how to filter actions for each users? How to store the action events? Which data model and object model can I use for the actions stream and for the actions it...
Oracle SQL: Update a table with data from another table
...ere is no matching row in t2. Without it, every row in t1 will be updated and the values will be set to NULL if there is no matching row in t2. That is generally not what you want to happen so the WHERE EXISTS is generally needed.
– Justin Cave
Aug 5 '13 at 1...
MYSQL OR vs IN performance
... not believe people who give their "opinion", science is all about testing and evidence.
I ran a loop of 1000x the equivalent queries (for consistency, I used sql_no_cache):
IN: 2.34969592094s
OR: 5.83781504631s
Update:
(I don't have the source code for the original test, as it was 6 years ago, ...
get an element's id
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@Rana - Yup, it's a DOM element property, and all specific elements inherit from the basic dom element, so they have the property :)
– Nick Craver♦
Sep 2 '10 at 0:59
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IN clause and placeholders
I'm attempting to do the following SQL query within Android:
9 Answers
9
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Explicitly set Id with Doctrine when using “AUTO” strategy
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Thank you and I'm happy to help a bit as I can :)
– nicolasbui
Dec 5 '12 at 18:20
2
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Rails find record with zero has_many records associated [duplicate]
... answered Mar 8 '12 at 6:31
AndrewAndrew
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How to remove item from list in C#?
...s {
public int ID; public string FirstName; public string LastName;
}
and assigned some values to results as follows:
var results=new List<myClass> {
new myClass() { ID=1, FirstName="Bill", LastName="Smith" },
new myClass() { ID=2, FirstName="John", LastName="Wilson" },
new ...