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{!join from=personid to=id fromIndex=AddressCore}address:Address1 So if you have two cores that look like this: PersonCore - id, name AddressCore - id, address, personid This will find all PersonCore documents at a specific address
It is often useful for debugging purposes to find the root cause of an error. In order to examine an error value that implements std::error::Error: use std::error::Error; let orig_error = call_returning_error(); // Use an Option<&Error>. This is the return type of Error.cause(). le...
$ git log -L 1,20:index.html commit 6a57fde739de66293231f6204cbd8b2feca3a869 Author: John Doe <[email protected]> Date: Tue Mar 22 16:33:42 2016 -0500 commit message diff --git a/index.html b/index.html --- a/index.html +++ b/index.html @@ -1,17 +1,20 @@ <!DOCTYPE HTML> ...
pass is a null statement for when a statement is required by Python syntax (such as within the body of a for or while loop), but no action is required or desired by the programmer. This can be useful as a placeholder for code that is yet to be written. for x in range(10): pass #we don't want t...
You can use an environment filter to change the author of commits. Just modify and export $GIT_AUTHOR_NAME in the script to change who authored the commit. Create a file filter.sh with contents like so: if [ "$GIT_AUTHOR_NAME" = "Author to Change From" ] then export GIT_A...
Screen shot: Option 1 (pure adb) The shell adb command allows us to execute commands using a device's built-in shell. The screencap shell command captures the content currently visible on a device and saves it into a given image file, e.g. /sdcard/screen.png: adb shell screencap /sdcard/screen.png...
4.4 Recording the display of devices running Android 4.4 (API level 19) and higher: adb shell screenrecord [options] <filename> adb shell screenrecord /sdcard/demo.mp4 (press Ctrl-C to stop recording) Download the file from the device: adb pull /sdcard/demo.mp4 Note: Stop the scre...
Since Unity 5.2.5 it's possible to use RuntimeInitializeOnLoadMethodAttribute to execute initialization logic bypassing MonoBehaviour order of execution. It provides a way to create more clean and robust implementation: using UnityEngine; sealed class GameDirector : MonoBehaviour { // Beca...
The reason you do not have to override Awake, Start, Update and other method is because they are not virtual methods defined in a base class. The first time your script gets accessed, the scripting runtime looks through the script to see if some methods are defined. If they are, that information is...
Example method in controller @RequestMapping(value = "/test") public String showCheckbox(Model model) { boolean myBooleanVariable = false; model.addAttribute("myBooleanVariable", myBooleanVariable); return "sample-checkbox"; } View: sample-checkbox....
To forbid null values in your table columns, add the :null parameter to your migration, like this: class AddPriceToProducts < ActiveRecord::Migration def change add_column :products, :float, null: false end end
You may want to nest cached fragments inside other cached fragments. This is called Russian doll caching. The advantage of Russian doll caching is that if a single product is updated, all the other inner fragments can be reused when regenerating the outer fragment. As explained in the previous sec...
Query caching is a Rails feature that caches the result set returned by each query. If Rails encounters the same query again for that request, it will use the cached result set as opposed to running the query against the database again. For example: class ProductsController < ApplicationControl...
On the profile view, show the profile fields of a user or group in a list as well as the address fields on a google map. - # app/views/profiles/show.html.haml %h1 Contact Information .profile_fields = render @profile_fields .google_map{data: address_fields: @address_fields.to_json } The ap...
Suppose, there is a .google_map div, which will become the map, and which has the address fields to show as markers as data attribute. For example: <!-- http://localhost:3000/profiles/123 --> <div class="google_map" data-address-fields="[ {label: 'Work address', value: ...
Provided an App.GoogleMap coffee script class, the google map can be initialized like this: # app/assets/javascripts/google_maps.js.coffee # ... class App.GoogleMap map_div: {} map: {} constructor: (map_div)-> @map_div = map_div @init_map() @reference_the_map_as_dat...
Provided an App.GoogleMap coffee script class and the marker information being stored in the data-address-fields attribute of the .google_map div, the map markers can be initialized on the map like this: # app/assets/javascripts/google_maps.js.coffee # ... class App.GoogleMap # ... markers:...
Provided an App.GoogleMap coffee script class with the google.maps.Map stored as @map and the google.maps.Markers stored as @markers, the map can be auto-zoomed, i.e. adjusted that all markers are visible, like this: on the map like this: # app/assets/javascripts/google_maps.js.coffee # ... cla...
To display address profile fields as markers on a google map, the address field objects need to be passed as json objects to javascript. Regular database attributes When calling to_json on an ApplicationRecord object, the database attributes are automatically exposed. Given a ProfileFields::Addre...
If you need to search an ActiveRecord model for similar values, you might be tempted to use LIKE or ILIKE but this isn't portable between database engines. Similarly, resorting to always downcasing or upcasing can create performance issues. You can use ActiveRecord's underlying Arel matches method...

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