Marks Notes

console.table(variable-name)

console.trace()

console.error() and console.warn()

console.count() and console.countReset()

console.time(), console.timeEnd(), and console.timeLog()

console.clear()

// from https://releases.jquery.com/ ?? do we really need the https: part ???

[ ‘https://code.jquery.com/jquery-3.6.0.js’
].forEach( (src) => { let script = document.createElement(‘script’); script.src = src; script.async = false; document.head.appendChild(script);
});

to remove rule:

stylesheet.deleteRule(index),

(loop to find the right value)

==========================================================

// https://webplatform.github.io/docs/tutorials/Dynamic_style_-_manipulating_CSS_with_JavaScript/
// https://stackoverflow.com/questions/70251599/how-to-use-cssstylesheet-insertrule-to-change-a-root-property/71875353

to manipulate the “—” rules such as “—marksVariableName, it has to be done in the” selector and use insertRule:”

this should turn the background color from red to whatever value is in the hash.

2022-04-01:

function tryMe({one, two, three}) { console.log(one, two,three) ; }

const tmp = { one: 1, two: 2, three: 3 } ;

tryMe(tmp) ;

=========================================

https://www.sitepoint.com/community/t/promises-feedback/384246/3

consider passing an JSON object for parms in the future:

function tester({param}) { console.log(JSON.stringify(param));
}
tester({param: { ‘parmOne’: 123, ‘paramTwo’: “two”}}) ;

===========

REPLACE:

function desiredCar(eachCar) { const make = eachCar.make; const model = eachCar.model; const hp = eachCar.hp; // then do stuff with make, model, and hp
}

WITH:

function desiredCar({make, model, hp}) {

}

=======

knex examples to replace sequelize.

first create knex user:
DROP USER IF EXISTS ‘knexUser’@‘localhost’ ;
CREATE USER ‘knexUser’@‘localhost’ IDENTIFIED BY ‘knexPassword’;

GRANT ALL ON `comptonTransAnlys`.* TO ‘knexUser’@‘localhost’
IDENTIFIED BY ‘knexPassword’ WITH MAX_QUERIES_PER_HOUR 0
MAX_CONNECTIONS_PER_HOUR 0 MAX_UPDATES_PER_HOUR 0 MAX_USER_CONNECTIONS 0 ;

GRANT ALL PRIVILEGES ON `comptonTransAnlys`.* TO ‘knexUser’@‘localhost’ ;

1. mariadb —host=localhost —user=knexUser —password=knexPassword comptonTransAnlys ;

// https://zetcode.com/javascript/knex/

// mariadb —host=localhost —user=knexUser —password=knexPassword knexDb ;

const knexConnectOptions = { client: ‘mysql’, debug: true, connection: { host : ‘localhost’, port : 3306, user : ‘knexUser’, password : ‘knexPassword’, database : ‘knexDb’ }
};

const knex = require(‘knex’)(knexConnectOptions);

knex.raw(“SELECT VERSION”) .then ( (version) => console.log((version⁰⁰)) ) .catch((err) => { console.log( err); throw err }) .finally(() => { knex.destroy(); });

knex.schema .createTable(‘cars’, (table) => { table.increments(‘id’) ; table.string(‘name’) ; table.integer(‘price’) ; }) .then(() => console.log(“table created”)) .catch((err) => { console.log(err); throw err }) .finally(() => { knex.destroy(); process.exit(); });

const cars = [ { name: ‘Audi’, price: 52642 }, { name: ‘Mercedes’, price: 57127 }, { name: ‘Skoda’, price: 9000 }, { name: ‘Volvo’, price: 29000 }, { name: ‘Bentley’, price: 350000 }, { name: ‘Citroen’, price: 21000 }, { name: ‘Hummer’, price: 41400 }, { name: ‘Volkswagen’, price: 21600 },
]

knex.from(‘cars’) // or just knex(‘cars’) .insert(cars) .then((id) => console.log(“data inserted: “ + id ) /* note display of returned ID! */ .catch((err) => { console.log(err); throw err }) .finally(() => { knex.destroy(); process.exit(); });

knex.from(‘cars’) // or just knex(‘cars’) .select(“*”) .where (true) // optional! .then((rows) => { for (row of rows) { console.log(`${row[‘id’]} ${row[‘name’]} ${row[‘price’]}`); } }).catch((err) => { console.log( err); throw err }) .finally(() => { knex.destroy(); process.exit(); });

knex.from(‘cars’) // or just knex(‘cars’) .select(“name”, “price”).where(‘price’, ‘>’, ‘50000’) .where (true) .then((rows) => { for (row of rows) { console.log(`${row[‘name’]} ${row[‘price’]}`); } }) .catch((err) => { console.log( err); throw err }) .finally(() => { knex.destroy(); process.exit(); });

// mariadb —host=localhost —user=knexUser —password=knexPassword knexDb ;

const knexConnectOptions = { client: ‘mysql’, debug: true, connection: ‘mysql://knexUser:knexPassword@localhost:3306/knexDb’
};

const knex = require(‘knex’)(knexConnectOptions);

knex(‘cars’) .where ({‘id’: 6 }) // OR .where (‘id’ , ‘=’, 6) .update({ name : ‘Toyota’}) /* notice {} */ .catch((err) => { console.log( err); throw err }) .finally(() => { knex.destroy(); process.exit(); });
// delete!
knex(‘cars’) .where (‘id’ , ‘=’, 6) .del() .catch((err) => { console.log( err); throw err }) .finally(() => { knex.destroy(); process.exit(); });

// short connection string:
const knexConnectOptions = { client: ‘mysql’, connection: ‘mysql://knexUser:knexPassword@localhost:3306/knexDb’
};

const knex = require(‘knex’)(knexConnectOptions);

knex.from(‘cars’) .select(“name”, “price”) .where(‘id’, ‘=’, ‘6’) .then((rows) => { for (row of rows) { console.log(`${row[‘name’]} ${row[‘price’]}`); } }) .catch((err) => { console.log( err); throw err }) .finally(() => { knex.destroy(); process.exit(); });