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How to get the top 10 values in postgresql?
... *,
rank() over (order by some_value_column desc) as my_rank
from mytable) subquery
where my_rank <= 10
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How to prevent ifelse() from turning Date objects into numeric objects
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You may use data.table::fifelse (data.table >= 1.12.3) or dplyr::if_else.
data.table::fifelse
Unlike ifelse, fifelse preserves the type and class of the inputs.
library(data.table)
dates <- fifelse(dates == '2011-01-01', dates - 1, d...
UITableViewCell Separator disappearing in iOS7
I have some strange issue with UITableView only in iOS 7.
37 Answers
37
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UITableView + Add content offset at top
I need to add some blank space to the top of my UITableView that does not affect the size of the content area. Shifting the content down or adding a blank cell is NOT what I want to do. Instead I just want an offset.
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How to link to part of the same document in Markdown?
I am writing a large Markdown document and would like to place a table of contents of sorts at the beginning that will provide links to various locations in the document. How can I do this?
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MySQL stored procedure vs function, which would I use when?
...hilst with stored function you can.
e.g. SELECT get_foo(myColumn) FROM mytable is not valid if get_foo() is a procedure, but you can do that if get_foo() is a function. The price is that functions have more limitations than a procedure.
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Most underused data visualization [closed]
...d.date <- Sys.Date()
quote <- paste("http://ichart.finance.yahoo.com/table.csv?s=",
stock, "&a=", substr(start.date,6,7),
"&b=", substr(start.date, 9, 10),
"&c=", substr(start.date, 1,4),
"&d=", substr(end.date,6,...
iOS 7 TableView like in Settings App on iPad
I want to have a group UITableView with the style same like the iPad Settings application Detail view for iOS 7 .
15 Ans...
I need to generate uuid for my rails application. What are the options(gems) I have? [duplicate]
... the column.
Example in Rails 3 migration
execute <<-SQL
CREATE TABLE some_items (id uuid PRIMARY KEY DEFAULT uuid_generate_v1());
SQL
Might be a better way to do this in Rails 4.
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MySQL: @variable vs. variable. What's the difference?
...t work because my_var is not a system variable, whereas we can do set@@big_tables=1, set@@session.big_tables=1, and set session big_tables=1 because big_tables is a system variable.
– Pacerier
May 24 '15 at 23:10
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