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Haskell: Lists, Arrays, Vectors, Sequences

... up performance tends to come from [Char] which the prelude has aliased as String. Char lists are convient, but tend to run on the order of 20 times slower than C strings, so feel free to use Data.Text or the very fast Data.ByteString. I'm sure there are other sequence oriented libraries I'm not t...
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Check if a row exists, otherwise insert

... can be worked around with a kind of double checked locking via preventive extra exists check without locking hints. – Vadzim May 14 '18 at 19:36 ...
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What are the differences between a multidimensional array and an array of arrays in C#?

...using System; using System.Diagnostics; static class ArrayPref { const string Format = "{0,7:0.000} "; static void Main() { Jagged(); Multi(); Single(); } static void Jagged() { const int dim = 100; for(var passes = 0; passes < 10; ...
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What does the Reflect object do in JavaScript?

...r property update. For instance: var name = ... // get property name as a string obj[name] // generic property lookup obj[name] = value // generic property update The Reflect.get and Reflect.set methods allow you to do the same thing, but additionally accept as a last optional argument a receiver...
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Entity Framework 5 Updating a Record

...hen to call, for example: public void UpdatePasswordAndEmail(long userId, string password, string email) { var user = new User {UserId = userId, Password = password, Email = email}; Update(user, u => u.Password, u => u.Email); Save(); } I like one trip to the database. Its pro...
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Comparison of full text search engine - Lucene, Sphinx, Postgresql, MySQL?

.... <uniqueKey>id</uniqueKey> <field name="solr_name" type="string" indexed="true" stored="true" /> Implementation Indexing This is where the real deal is. You need to do the indexing of data from MySQL to Solr inorder to make use of Solr Queries. Step 1: Go to Solr Admin ...
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Create table (structure) from existing table

... This solution is clearer than having the extra condition "1 = 2", I would recommend this – Pinte Dani Oct 2 '19 at 5:58 add a comment ...
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How do I correctly clone a JavaScript object?

...*/ setTimeout(function(){ var d2 = clone(d1); alert("d1 = " + d1.toString() + "\nd2 = " + d2.toString()); }, 5000); The date string for d1 will be 5 seconds behind that of d2. A way to make one Date the same as another is by calling the setTime method, but that is specific to the Date clas...
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How do you crash a JVM?

...Hotspot VM quiet nicely: public class Crash { public static void main(String[] args) { Object[] o = null; while (true) { o = new Object[] {o}; } } } This leads to a stack overflow in the GC so you will get no StackOverflowError but a real crash includi...
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How to add local jar files to a Maven project?

...he project will just work as if the jars were in maven central without any extra manual steps. – opticyclic Jun 27 '16 at 23:34 9 ...