prologic

Learn Go in ~5mins

This is inspired by A half-hour to learn Rust and Zig in 30 minutes.

Basics

Your first Go program as a classical "Hello World" is pretty simple:

First we create a workspace for our project:

andreyvit

tmux cheat sheet

(C-x means ctrl+x, M-x means alt+x)

Prefix key

The default prefix is C-b. If you (or your muscle memory) prefer C-a, you need to add this to ~/.tmux.conf:

remap prefix to Control + a

tylerneylon

-- Two dashes start a one-line comment.

--[[
     Adding two ['s and ]'s makes it a
     multi-line comment.
--]]

----------------------------------------------------
-- 1. Variables and flow control.
----------------------------------------------------

mikeyk

#! /usr/bin/env python

import redis
import random
import pylibmc
import sys

r = redis.Redis(host = 'localhost', port = 6389)
mc = pylibmc.Client(['localhost:11222'])

marwei

Kafka 0.11.0.0 (Confluent 3.3.0) added support to manipulate offsets for a consumer group via cli kafka-consumer-groups command.

1. List the topics to which the group is subscribed

kafka-consumer-groups --bootstrap-server <kafkahost:port> --group <group_id> --describe

Note the values under "CURRENT-OFFSET" and "LOG-END-OFFSET". "CURRENT-OFFSET" is the offset where this consumer group is currently at in each of the partitions.

2. Reset the consumer offset for a topic (preview)

MineRobber9000

###########################################################
# How to NEVER use lambdas. An inneficient and yet educa- #
# tonal [sic] guide to the proper misuse of the lambda    #
# construct in Python 3.x.  [DO NOT USE ANY OF THIS EVER] #
#          original by (and apologies to): e000 (13/6/11) #
#           now in Python 3 courtesy of: khuxkm (17/9/20) #
###########################################################

## Part 1. Basic LAMBDA Introduction ##
# If you're reading this, you've probably already read e000's

longcao

import java.io.InputStream

import org.apache.spark.sql.execution.datasources.jdbc.JdbcUtils
import org.apache.spark.sql.{ DataFrame, Row }

import org.postgresql.copy.CopyManager
import org.postgresql.core.BaseConnection

val jdbcUrl = s"jdbc:postgresql://..." // db credentials elided
val connectionProperties = {

joe-pindell

set thePath to (path to desktop as Unicode text) & "ThingsToDo.txt"
set thingsToDoFile to (open for access file thePath with write permission)
set eof of thingsToDoFile to 0
set cr to ASCII character 10

tell application "Things"
	
	-- Export to-dos from Inbox
	write "Inbox:" & return to thingsToDoFile as «class utf8»
	repeat with td in to dos of list "Inbox"

hgmnz

Types of index scans

Indexes

Sequential Scan:

• Read every row in the table
• No reading of index. Reading from indexes is also expensive.

baopham