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This option makes JRockit JVM exit on the first occurrence of an out of memory error. It can be used if you prefer restarting an instance of JRockit JVM rather than handling out of memory errors. Enter this command at startup to force JRockit JVM to exit on the first occurrence of an out of memory e...

When a page is part of a series of articles, for instance, one can use prev and next to point to pages that are coming before and after. <link rel="prev" href="http://stackoverflow.com/documentation/java/topics"> <link rel="next" href="http://stackover...

Create a select list that can be used to choose a single or multiple items from a list of values. library(shiny) ui <- fluidPage( selectInput("id_selectInput", label = HTML('<B><FONT size="3">What is your favorite color ?</FONT></B&g...

When a function returns an object (as opposed to using one that's passed in by the caller), be careful an exception doesn't cause the object to leak. function MakeStrings: TStrings; begin // Create a new object before entering the try-block. Result := TStringList.Create; try // Execu...

A try-finally block may be nested inside a try-except block. try AcquireResources; try UseResource; finally ReleaseResource; end; except on E: EResourceUsageError do begin HandleResourceErrors; end; end; If an exception occurs inside UseResource, then execution...

A try-except block may be nested inside a try-finally block. AcquireResource; try UseResource1; try UseResource2; except on E: EResourceUsageError do begin HandleResourceErrors; end; end; UseResource3; finally ReleaseResource; end; If an EResourceUsageE...

When using clustered index, the rows of the table are sorted by the column to which the clustered index is applied. Therefore, there can be only one clustered index on the table because you can't order the table by two different columns. Generally, it is best to use clustered index when performing ...

Nonclustered indexes are stored separately from the table. Each index in this structure contains a pointer to the row in the table which it represents. This pointers are called a row locators. The structure of the row locator depends on whether the data pages are stored in a heap or a clustered tab...

Below code showcases multiple Producer/Consumer program. Both Producer and Consumer threads share same global queue. import java.util.concurrent.*; import java.util.Random; public class ProducerConsumerWithES { public static void main(String args[]) { BlockingQueue<Integer> ...

// Default export export default {}; // Named export export const SomeVariable = {};

In your mainModule file: export const SomeVar = {};

class Product(models.Model): name = models.CharField(max_length=20) price = models.FloatField() To Get average price of all products: >>> from django.db.models import Avg, Max, Min, Sum >>> Product.objects.all().aggregate(Avg('price')) # {'price__avg': 124.0} To ...

Most performance tips are very dependent of the current state of JS engines and are expected to be only relevant at a given time. The fundamental law of performance optimization is that you must first measure before trying to optimize, and measure again after a presumed optimization. To measure cod...

Javascript engines first look for variables within the local scope before extending their search to larger scopes. If the variable is an indexed value in an array, or an attribute in an associative array, it will first look for the parent array before it finds the contents. This has implications wh...

Open index.ios.js or index.android.js and delete everything between the <View> </View>. After that, write <Text> Hello World! </Text> and run the emulator. You should see Hello World! written on the screen! Congrats! You've successfully written your first Hello World!

Basic syntax DT[where, select|update|do, by] syntax is used to work with columns of a data.table. The "where" part is the i argument The "select|update|do" part is the j argument These two arguments are usually passed by position instead of by name. A sequence of steps c...

xml_import_example.info.yml type: module name: XML import example package: Examples description: "This module helps understanding the Batch API and Queue API with an XML import example" core: 8.x xml_import_example.permissions.yml import content from xml: title: 'Import content...

2.02 Preparation $ mkdir globbing $ cd globbing $ mkdir -p folder/{sub,another}folder/content/deepfolder/ touch macy stacy tracy "file with space" folder/{sub,another}folder/content/deepfolder/file .hiddenfile $ shopt -u nullglob $ shopt -u failglob $ shopt -u dotglob $ shopt -u n...

By overloading the indexer you can create a class that looks and feels like an array but isn't. It will have O(1) get and set methods, can access an element at index 100, and yet still have the size of the elements inside of it. The SparseArray class class SparseArray { Dictionary<...

const namedMember1 = ... const namedMember2 = ... const namedMember3 = ... export { namedMember1, namedMember2, namedMember3 }