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How to map and remove nil values in Ruby
...blem:
N = 1_00_000
enum = 1.upto(1_000)
Benchmark.bmbm do |x|
x.report("select + map") { N.times { enum.select { |i| i.even? }.map{|i| i + 1} } }
x.report("map + compact") { N.times { enum.map { |i| i + 1 if i.even? }.compact } }
x.report("filter_map") { N.times { enum.filter_map { |i| i ...
Combine Date and Time columns using python pandas
...etime64[ns]
Note: surprisingly (for me), this works fine with NaNs being converted to NaT, but it is worth worrying that the conversion (perhaps using the raise argument).
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How do I get IntelliJ IDEA to display directories?
...correctly. Make sure the "Content Root" is correct.
Click on the project
Select "File"->"Project Structure"
Select "modules" from the left column, and select a module.
On the sources tab you will see the current "Content Root" along with a button to add a new content root.
Make sure that con...
ServiceStack vs ASP.Net Web API [closed]
...t (IHttpResult) for Customized HTTP response
The following types are not converted and get written directly to the Response Stream:
String
Stream
IStreamWriter
byte[] - with the application/octet-stream Content Type.
An example of the Custom HTTP headers support can be seen by this CORS exampl...
Async/await vs BackgroundWorker
...e DoWork, RunWorkerCompleted, and ProgressChanged event handlers.
If you "converted" that to async/await, you'd do something like:
IProgress<int> progress = new Progress<int>();
progress.ProgressChanged += ( s, e ) =>
{
// TODO: do something with e.Prog...
Reverse of JSON.stringify?
...
I read the OP as saying "I converted a javascript object to a JSON string, and now I want to convert it back - how do I do it?" All the other answers say just use JSON.parse. I'm just warning that theres a lot of cases that will not handle correctly. I...
Why would someone use WHERE 1=1 AND in a SQL clause?
...mple code to Greg's answer:
dim sqlstmt as new StringBuilder
sqlstmt.add("SELECT * FROM Products")
sqlstmt.add(" WHERE 1=1")
''// From now on you don't have to worry if you must
''// append AND or WHERE because you know the WHERE is there
If ProductCategoryID <> 0 then
sqlstmt.AppendForm...
Find rows with multiple duplicate fields with Active Record, Rails & Postgres
...
Tested & Working Version
User.select(:first,:email).group(:first,:email).having("count(*) > 1")
Also, this is a little unrelated but handy. If you want to see how times each combination was found, put .size at the end:
User.select(:first,:email).gro...
How do I put an 'if clause' in an SQL string?
... WHERE purchaseOrder_ID = '@purchaseOrder_ID' and
not exists (SELECT *
FROM itemsOrdered WHERE purchaseOrder_ID = '@purchaseOrdered_ID' AND status = 'PENDING'
)
However, I might guess that you are looping at a higher level. To set all such v...
Check if a temporary table exists and delete if it exists before creating a temporary table
...me in SQL Server 2005, with the extra "foo" column appearing in the second select result:
IF OBJECT_ID('tempdb..#Results') IS NOT NULL DROP TABLE #Results
GO
CREATE TABLE #Results ( Company CHAR(3), StepId TINYINT, FieldId TINYINT )
GO
select company, stepid, fieldid from #Results
GO
ALTER TABLE #R...