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Questions tagged [intersect]

The SQL intersect operator returns rows that are common between two tables without returning duplicate records.

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The opposite of Intersect()

Intersect can be used to find matches between two collections, like so: // Assign two arrays. int[] array1 = { 1, 2, 3 }; int[] array2 = { 2, 3, 4 }; // Call Intersect extension method. var intersect = array1.Intersect(array2); // Write intersection…
Peter Bridger
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Finding common rows (intersection) in two Pandas dataframes

Assume I have two dataframes of this format (call them df1 and df2): +------------------------+------------------------+--------+ | user_id | business_id | rating…
David Chouinard
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How do I compute the intersection point of two lines?

I have two lines that intersect at a point. I know the endpoints of the two lines. How do I compute the intersection point in Python? # Given these endpoints #line 1 A = [X, Y] B = [X, Y] #line 2 C = [X, Y] D = [X, Y] # Compute…
bolt19
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Alternative to Intersect in MySQL

I need to implement the following query in MySQL. (select * from emovis_reporting where (id=3 and cut_name= '全プロセス' and cut_name='恐慌') ) intersect ( select * from emovis_reporting where (id=3) and ( cut_name='全プロセス' or cut_name='恐慌') ) I know that…
Ankur Jariwala
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INTERSECT in MySQL

I have two tables, records and data. records has multiple fields (firstname, lastname, etc.). Each of these fields is a foreign key for the data table where the actual value is stored. I need to search on multiple record fields. Below is an…
user277421
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How can I check if a Ruby array includes one of several values?

I have two Ruby arrays, and I need to see if they have any values in common. I could just loop through each of the values in one array and do include?() on the other, but I'm sure there's a better way. What is it? (The arrays both hold…
Colen
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Is there a fundamental difference between INTERSECT and INNER JOIN?

I understand, that INNER JOIN is made for referenced keys and INTERSECT is not. But afaik in some cases, both of them can do the same thing. So, is there a difference (in performance or anything) between the following two expressions? And if there…
Jere
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C# Linq intersect/except with one part of object

I've got a class: class ThisClass { private string a {get; set;} private string b {get; set;} } I would like to use the Intersect and Except methods of Linq, i.e.: private List foo = new List(); private List bar…
David Archer
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Count items existing in 2 Lists

I have two int type List like List A and List B. I want to check how many items of List A are there in List B. I am able to do this, but what can be an efficient way as I am trying to avoid foreach, as optimization is a prime target in my…
Incredible
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Opposite of intersect in groovy collections

what would be the opposite of intersect in groovy collections?
Espen Schulstad
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Force MySQL to use two indexes on a Join

I am trying to force MySQL to use two indexes. I am joining a table and I want to utilize the cross between the two indexes. The specific term is Using intersect and here is a link to MySQL documentation:…
Spencer
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Intersecting Points and Polygons in R

I am working with shapefiles in R, one is point.shp the other is a polygon.shp. Now, I would like to intersect the points with the polygon, meaning that all the values from the polygon should be attached to the table of the point.shp. I tried…
Jens
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c# dictionaries intersect

I have a question about Linq / Lambda and the following issue: I have two dictionaries, primary and secondary... These two dictionaries are defined as Key=string, Value=int. I need to trim down the primary dictionary if the KEYS intersect with…
Stewart Basterash
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Python list intersection efficiency: generator or filter()?

I would like to intersect two lists in Python (2.7). I need the result to be iterable: list1 = [1,2,3,4] list2 = [3,4,5,6] result = (3,4) # any kind of iterable Providing a full iteration will be performed first thing after the intersection, which…
Amnon Grossman
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Trying to understand "except all" in sql query

I came across this example and I don't understand what it means. (SELECT drinker FROM Frequents) EXCEPT ALL (SELECT drinker FROM Likes); relations: Frequents(drinker, bar), Likes(drinker, beer) What does the ALL do in this case? How is the…
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