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How do I limit the number of rows returned by an Oracle query after ordering?

... the original question, here's the query: SELECT * FROM sometable ORDER BY name OFFSET 20 ROWS FETCH NEXT 10 ROWS ONLY; (For earlier Oracle versions, please refer to other answers in this question) Examples: Following examples were quoted from linked page, in the hope of preventing link rot. Se...
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find() with nil when there are no records

... Yes, just do: Challenge.find_by_id(10) For Rails 4 and 5: Challenge.find_by(id: 10) share | improve this answer | follow ...
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Understanding the ngRepeat 'track by' expression

I'm having difficulties understanding how the track by expression of ng-repeat in angularjs works. The documentation is very scarce: http://docs.angularjs.org/api/ng/directive/ngRepeat ...
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ORDER BY the IN value list

... (3,2), (2,3), (4,4) ) as x (id, ordering) on c.id = x.id order by x.ordering share | improve this answer | follow | ...
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how to remove X-Powered-By in ExpressJS [duplicate]

I want to remove X-Powered-By for Security,Save Bandwidth in ExpressJS(node.js). how to do it? it could be filter(app.use) ? ...
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Passing Objects By Reference or Value in C#

In C#, I have always thought that non-primitive variables were passed by reference and primitive values passed by value. 7 ...
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Relative frequencies / proportions with dplyr

...rs data, how do I calculate the relative frequency of number of gears by am (automatic/manual) in one go with dplyr ? ...
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Simultaneously merge multiple data.frames in a list

...concise syntax: library(tidyverse) list(x, y, z) %>% reduce(left_join, by = "i") # A tibble: 3 x 4 # i j k l # <chr> <int> <int> <int> # 1 a 1 NA 9 # 2 b 2 4 NA # 3 c 3 5 7 You can also perform other joins, such as a...
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Swift: Pass array by reference?

...nt to pass my Swift Array account.chats to chatsViewController.chats by reference (so that when I add a chat to account.chats , chatsViewController.chats still points to account.chats ). I.e., I don't want Swift to separate the two arrays when the length of account.chats changes. ...
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Retrieving the last record in each group - MySQL

...ies: WITH ranked_messages AS ( SELECT m.*, ROW_NUMBER() OVER (PARTITION BY name ORDER BY id DESC) AS rn FROM messages AS m ) SELECT * FROM ranked_messages WHERE rn = 1; Below is the original answer I wrote for this question in 2009: I write the solution this way: SELECT m1.* FROM messages...