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@zafergurel
zafergurel / postgres_queries_and_commands.sql
Last active June 10, 2024 13:39 — forked from rgreenjr/postgres_queries_and_commands.sql
Useful PostgreSQL Queries and Commands
-- https://www.geekytidbits.com/performance-tuning-postgres/
-- http://www.craigkerstiens.com/2012/10/01/understanding-postgres-performance/
-- http://okigiveup.net/what-postgresql-tells-you-about-its-performance/
-- https://wiki.postgresql.org/wiki/Introduction_to_VACUUM,_ANALYZE,_EXPLAIN,_and_COUNT
-- https://devcenter.heroku.com/articles/postgresql-indexes#b-trees-and-sorting
-- http://www.databasesoup.com/2014/05/new-finding-unused-indexes-query.html
-- performance tools
-- https://www.vividcortex.com/resources/network-analyzer-for-postgresql
-- show running queries (pre 9.2)
@tkrotoff
tkrotoff / FrontendFrameworksPopularity.md
Last active November 19, 2025 21:09
Front-end frameworks popularity (React, Vue, Angular and Svelte)
@marwei
marwei / how_to_reset_kafka_consumer_group_offset.md
Created November 9, 2017 23:39
How to Reset Kafka Consumer Group Offset

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.

  1. Reset the consumer offset for a topic (preview)
"use strict";
// Registering cleanup callback before requiring flightplan.
process.on("SIGINT", interruptedCleanup);
const util = require("util"),
moment = require("moment"),
_ = require("lodash"),
plan = require("flightplan"),
request = require("request-promise");

Parens And Performance

Years ago, some smart folks that worked on JS engines realized that not all JS that's loaded into a page/app initially is needed right away. They implemented JIT to optimize this situation.

JIT means Just-In-Time, which means essentially that the engine can defer processing (parsing, compiling) certain parts of a JS program until a later time, for example when the function in question is actually needed. This deferral means the engine is freer to spend the important cycles right now on the code that's going to run right now. This is a really good thing for JS performance.

Some time later, some JS engine devs realized that they needed to get some hints from the code as to which functions would run right away, and which ones wouldn't. In technical speak, these hints are called heuristics.

So they realized that one very common pattern for knowing that a function was going to run right away is if the first character before the function keyword was a (, because that usually m

@ursuad
ursuad / kafka-cheat-sheet.md
Last active June 17, 2025 10:00
Quick command reference for Apache Kafka

Kafka Topics

List existing topics

bin/kafka-topics.sh --zookeeper localhost:2181 --list

Describe a topic

bin/kafka-topics.sh --zookeeper localhost:2181 --describe --topic mytopic

Purge a topic

bin/kafka-topics.sh --zookeeper localhost:2181 --alter --topic mytopic --config retention.ms=1000

... wait a minute ...

@olih
olih / jq-cheetsheet.md
Last active December 5, 2025 21:17
jq Cheet Sheet

Processing JSON using jq

jq is useful to slice, filter, map and transform structured json data.

Installing jq

On Mac OS

brew install jq

@jackcarter
jackcarter / slack_delete.py
Last active September 7, 2025 07:08
Delete Slack files older than 30 days. Rewrite of https://gist.github.com/jamescmartinez/909401b19c0f779fc9c1
import requests
import time
import json
token = ''
#Delete files older than this:
ts_to = int(time.time()) - 30 * 24 * 60 * 60
def list_files():