Md. Sany Ahmed sany2k8

Quick Decision Tree

(Create a symlink pytest for py.test)

pytest [options] [file_or_dir] [file_or_dir] ...

Help:

command -v nvm

nvm current -- or -- node -v

Don’t SELECT *, Specify explicit column names (columnar store)
Avoid large JOINs (filter each table first)
- In PRESTO tables are joined in the order they are listed!!
- Join small tables earlier in the plan and leave larger fact tables to the end
- Avoid cross joins or 1 to many joins as these can degrade performance
Order by and group by take time
- only use order by in subqueries if it is really necessary
When using GROUP BY, order the columns by the highest cardinality (that is, most number of unique values) to the lowest.

	variable "env_level" {
	description = "Environment level"
	default = "dev"
	}

	module "eventbridge_price" {
	source = "terraform-aws-modules/eventbridge/aws"
	create_bus = false
	create_connections = true
	create_api_destinations = true

	import phonenumbers
	from pydantic.validators import strict_str_validator

	class PhoneNumber(str):
	"""Phone Number Pydantic type, using google's phonenumbers"""

	@classmethod
	def __get_validators__(cls):
	yield strict_str_validator
	yield cls.validate

	from typing import Any
	from typing import Dict
	from typing import Set
	from typing import Type

	from pydantic import SecretStr
	from pydantic.utils import update_not_none


	class Password(SecretStr):

	# best practice: linux
	nano ~/.pgpass
	:5432::username:password
	chmod 0600 ~/.pgpass

	# best practice: windows
	edit %APPDATA%\postgresql\pgpass.conf
	:5432::username:password

	# linux

	import asyncio
	import aiohttp
	import time


	async def gather_with_concurrency(n, *tasks):
	semaphore = asyncio.Semaphore(n)

	async def sem_task(task):
	async with semaphore:

	1) see re: increasing shmmax http://stackoverflow.com/a/10629164/1283020

	2) add to postgresql.conf:
	shared_preload_libraries = 'pg_stat_statements' # (change requires restart)
	136 pg_stat_statements.max = 1000
	137 pg_stat_statements.track = all

	3) restart postgres

	4) check it out in psql