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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

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<template>
    <div class="m-4 max-w-lg rounded overflow-hidden shadow-lg bg-white">
        <div class="p-4 max-w-xl" v-if="!connected" :key="updateModal">
            <h2 class="text-xl pb-9">Select one of the bellow options to perform a cryptocurrency transation via the ethereum test network.</h2>
            <div class="flex space-x-4">
                <button @click="checkWalletConnected" class="py-2 px-8 rounded button-custom flex"><img src="@/assets/logos/metamask-logo.png" class="w-6 mr-3" alt=""> Metamask</button>
                <button class="py-2 px-8 rounded button-custom disabled-custom flex"><img src="@/assets/logos/coinbase-logo.svg" class="w-6 mr-3" alt=""> Coinbase wallet</button>
            </div>
        </div>

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Steps to create Textured Mesh from Point Cloud using Meshlab

Get your PointCloud into MeshLab

• Import the pointcloud file in ".ply" file format in Meshlab. Before importing make sure you do some pre-processing / cleaning on point cloud so as to ease the process of meshing.

Point Cloud Simplification and Normals Computation

• Next we need to reduce the number of point samples for smooth meshing.
  • So go to Filters -> Point Set -> Point Cloud Simplification. Enter Number of samples circa 5% of original number of points. Make sure Best Sample Heuristic is checked.
• After point cloud simplification, make sure to select Simplified point cloud in the Show Layer Dialog on the right hand side. If not visible, it can be opened by navigating to View -> Show Layer Dialog. Now we need to compute normals for point set.
• So go to Filters -> Point Set -> Compute normals for point sets . Enter Neighbour num between 10 - 100. Initially try with 10 and

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#!/usr/bin/env python

import sys
import os
import subprocess

# Script taken from doing the needed operation
# (Filters > Remeshing, Simplification and Reconstruction >
# Quadric Edge Collapse Decimation, with parameters:
# 0.9 percentage reduction (10%), 0.3 Quality threshold (70%)

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#!/usr/bin/env python

import sys
import os
import subprocess

# Script taken from doing the needed operation
# (Filters > Remeshing, Simplification and Reconstruction >
# Quadric Edge Collapse Decimation, with parameters:
# 0.9 percentage reduction (10%), 0.3 Quality threshold (70%)

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SYSTEM

LENOVO IdeaPad 5 Pro 14ACN6 82L7

Enable conservation

Edit /etc/tlp.conf

~$ cat /etc/tlp.conf | grep STOP_CHARGE_THRESH_BAT0
STOP_CHARGE_THRESH_BAT0="1"

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INFURA_URL=<your_url>
ETHERSCAN_API_KEY=<your_api_key>

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AWS S3 bucket and IAM policy recipes

• Recipes
  • Anonymous GET access
  • Anonymous GET access - match HTTP referrer
  • Full access for specific IAM user/role
  • GET/PUT/DELETE access to specific path within a bucket
  • Restricted LIST & PUT/DELETE access to specific path within a bucket
  • Full access (and S3 console) for specific IAM users
  • Bucket and object delete deny
  • CloudTrail log receive

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/*
    MPU6050 Triple Axis Gyroscope & Accelerometer. Simple Accelerometer Example.
    Read more: http://www.jarzebski.pl/arduino/czujniki-i-sensory/3-osiowy-zyroskop-i-akcelerometr-mpu6050.html
    GIT: https://github.com/jarzebski/Arduino-MPU6050
    Web: http://www.jarzebski.pl
    (c) 2014 by Korneliusz Jarzebski
*/

#include <Wire.h>
#include <MPU6050.h>

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Secured HLS setup with Nginx as media server

This example is part of this article.

This is an example for an HLS delivery with basic security. Nginx compiled with nginx-rtmp-module & secure-link is used as media server. Features:

• Domain filtering
• Referrer filtering
• Embed buster