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Best way to select random rows PostgreSQL
...lass WHERE oid = 'schema_name.big'::regclass;
As long as ct isn't much smaller than id_span, the query will outperform other approaches.
WITH params AS (
SELECT 1 AS min_id -- minimum id <= current min id
, 5100000 AS id_span -- rounded up. (max_id - m...
How do I add a margin between bootstrap columns without wrapping [duplicate]
... Sep 25 '13 at 17:00
Charles IngallsCharles Ingalls
4,22755 gold badges2020 silver badges3232 bronze badges
...
Why are functions in Ocaml/F# not recursive by default?
...es (f1, f2 etc.) which pollutes the scope and makes it possible to accidentally invoke the wrong "version" of a function. And there is now a discrepancy between implicitly-recursive fun-bound functions and non-recursive val-bound functions.
Haskell makes it possible to infer the dependencies betwee...
MySQL > Table doesn't exist. But it does (or it should)
I changed the datadir of a MySQL installation and all the bases moved correctly except for one.
I can connect and USE the database. SHOW TABLES also returns me all the tables correctly, and the files of each table exists on the MySQL data directory.
...
Constants in Objective-C
...
Overall, great answer, with one glaring caveat: you DO NOT want to test for string equality with the == operator in Objective-C, since it tests memory address. Always use -isEqualToString: for this. You can easily get a different...
How can I use pointers in Java?
...
All objects in Java are references and you can use them like pointers.
abstract class Animal
{...
}
class Lion extends Animal
{...
}
class Tiger extends Animal
{
public Tiger() {...}
public void growl(){...}
}
Tiger fi...
pandas dataframe columns scaling with sklearn
...and I'd like to apply sklearn's min_max_scaler to some of the columns. Ideally, I'd like to do these transformations in place, but haven't figured out a way to do that yet. I've written the following code that works:
...
Pass an array of integers to ASP.NET Web API?
...iptor.GetConverter(elementType);
var values = Array.ConvertAll(s.Split(new[] { ","},StringSplitOptions.RemoveEmptyEntries),
x => { return converter.ConvertFromString(x != null ? x.Trim() : x); });
var typedValues = Array.CreateInstance(elementT...
How can I get nth element from a list?
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Personally I can't comprehend how an at-index accessor that doesn't return a Maybe type is acceptable as idiomatic Haskell. [1,2,3]!!6 will give you a runtime error. It could very easily be avoided if !! had the type [a] -> Int ...
How do I create a crontab through a script
... open an editor to edit the current crontab. I want to do this programmatically.
12 Answers
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