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/**
* Theory:
  -Classes use prototype-based inheritance
*/

/**
* Relevant Examples
*/

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/**
* Theory:
  -Arrays in JavaScript are an ordered collection of values
  -Its elements are untyped, an array can contain different types of data
  -Arrays are 32-bit indexed so its index can be from 0-4294967294 (2^32 - 2)
  and its elements can go from 0 to 4.294.967.295
*/

/**
* Relevant Examples

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const handsomeArray = [
"Option1",
"Option2",
"Option3", 
"Option4",
"Option5",
"Option6"
]

function * generatorFunction(array) { // Line 1

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/**
* When we do a freeze to an object, we only can read their items.
*/
const obj = {
  prop: 42
};

Object.freeze(obj);

obj.prop = 55;

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/**
* Explanation with an interview example from real life
* Call invokes the function and allows you to pass in arguments one by one.
* Apply invokes the function and allows you to pass in arguments as an array.
* Bind returns a new function, allowing you to pass in a this array and any number of arguments.
**/

// Call - Example
const callSomeone = (name, callback) => {
	const innerMessage= {

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// This validation is correct, because is not undefined neither zero
if(42){
  // Here we have a comparison without types (===) so, JS sees both as equals
	if(42 == "42"){
    // Correct
  	if(true){
      // This have no sense, because the callstack see the first item that is an integer, and can't compare
      // the boolean as a number
      if(42 == true){
        console.log("continue")

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FROM php:5.6-apache

RUN apt-get update
RUN apt-get install -y apt-utils
RUN apt-get install -y libpq-dev
RUN apt-get install -y mcrypt libmcrypt-dev
RUN apt-get install -y zlib1g-dev
RUN docker-php-ext-install pdo_pgsql pgsql mcrypt zip
RUN apt-get install nano

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Optimizing postgresql table for more than 100K inserts per second

• Create UNLOGGED table. This reduces the amount of data written to persistent storage by up to 2x.
• Set WITH (autovacuum_enabled=false) on the table. This saves CPU time and IO bandwidth on useless vacuuming of the table (since we never DELETE or UPDATE the table).
• Insert rows with COPY FROM STDIN. This is the fastest possible approach to insert rows into table.
• Minimize the number of indexes in the table, since they slow down inserts. Usually an index on time timestamp with time zone is enough.
• Add synchronous_commit = off to postgresql.conf.
• Use table inheritance for fast removal of old data:

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FROM nginx:alpine

RUN apk add --update npm

COPY nginx.conf /etc/nginx/conf.d/default.conf
COPY . /usr/local/app/

WORKDIR /usr/local/app/

RUN npm install

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/* Method to exclude items in a json, filtering by key index */
const excludeItemsInJson =
      (jsonObject: any, filterParams: ReadonlyArray<string>) =
        Object.keys(jsonObject)
          .filter((key: string) => filterParams.includes(key) ? false : true)
          .reduce((obj, item) => ({...obj, [item]: test[item]}) ,{})

/*  Method to allow items in a json, filtering by key index.
    Then a json will be returned with all the allowed items
*/