Igor Suhorukov igor-suhorukov

Awesome Electronic and Hardware platform

A curated list of amazingly awesome Electronic and Hardware platform #WoT #IoT #M2M

Awesome Electronic and Hardware platform

Storing some notes on getting WiFi access points working on BeagleBone Black with the latest Debian Jessie images using the 3.8 kernel.

Articles

Devices expected to work

RT2770F

SQL languages

DDL is short name of Data Definition Language, which deals with database schemas and descriptions, of how the data should reside in the database.

DML is short name of Data Manipulation Language which deals with data manipulation, and includes most common SQL statements such SELECT, INSERT, UPDATE, DELETE etc, and it is used to store, modify, retrieve, delete and update data in database.

DCL is short name of Data Control Language which includes commands such as GRANT, and mostly concerned with rights, permissions and other controls of the database system.

Datatypes

Text types

With Docker 1.8.0 shipped new log-driver for GELF via UDP, this means that the logs from Docker Container(s) can be shipped directly to the ELK stack for further analysis.
This tutorial will illustrate how to use the GELF log-driver with Docker engine.
Step 1: Setup ELK Stack:
- docker run -d --name es elasticsearch
- docker run -d --name logstash --link es:elasticsearch logstash -v /tmp/logstash.conf:/config-dir/logstash.conf logstash logstash -f /config-dir/logstash.conf
- Note the config for Logstash can be found at this link
- docker run --link es:elasticsearch -d kibana
Once the ELK stack is up now let's fire up our nginx container which ships its logs to ELK stack.

LOGSTASH_ADDRESS=$(docker inspect --format '{{ .NetworkSettings.IPAddress }}' logstash)
`docker run -d --net=host --log-driver=gelf --log-opt gelf-address=u

What is this all about?

This tutorial will turn your Raspberry PI into a simple Bluetooth audio receiver, which plays music through connected speakers. It's like a regular car audio system, but it can be used anywhere and it's a good value.

   Audio source (i.e. smartphone) 
                |
                v
 (((  Wireless Bluetooth Channel  )))
 |

Data URI SVG icons with Leaflet

Demonstrates how to load SVG's as Leaflet icons via the data URI method.

Following was helpful to figure this out:

	-- show running queries (pre 9.2)
	SELECT procpid, age(clock_timestamp(), query_start), usename, current_query
	FROM pg_stat_activity
	WHERE current_query != '<IDLE>' AND current_query NOT ILIKE '%pg_stat_activity%'
	ORDER BY query_start desc;

	-- show running queries (9.2)
	SELECT pid, age(clock_timestamp(), query_start), usename, query
	FROM pg_stat_activity
	WHERE query != '<IDLE>' AND query NOT ILIKE '%pg_stat_activity%'

	Below are the Big O performance of common functions of different Java Collections.


	List \| Add \| Remove \| Get \| Contains \| Next \| Data Structure
	---------------------\|------\|--------\|------\|----------\|------\|---------------
	ArrayList \| O(1) \| O(n) \| O(1) \| O(n) \| O(1) \| Array
	LinkedList \| O(1) \| O(1) \| O(n) \| O(n) \| O(1) \| Linked List
	CopyOnWriteArrayList \| O(n) \| O(n) \| O(1) \| O(n) \| O(1) \| Array

	Options:
	soundcloud.py --genre
	soundcloud.py search
	soundcloud.py user
	soundcloud.py tracks
	soundcloud.py url
	soundcloud.py playlist

	Usage:

	ssh -D 9999 root@REMOTE_IP

	google-chrome --proxy-server="socks5://127.0.0.1:9999" --host-resolver-rules="MAP * 0.0.0.0 , EXCLUDE 127.0.0.1"