Henning Bopp boppy

PostgreSQL DATE, TIMESTAMP, and INTERVAL cheat sheet

Working with DATE, TIMESTAMP, and INTERVAL in PostgreSQL can be confusing. In this article I will go over the three date/time related data types, and the two most useful date/time functions: DATE_PART and DATE_TRUNC. Finally, I will provide some real life examples of how these types and functions can be used within queries.

Types

PostgreSQL Date/Time Documentation

DATE

The DATE type contains the year, month, and day of a date. It is not possible to do any type of time related functions on a DATE without first converting it to a TIMESTAMP. Subtracting two DATE values from one another results in an INT representing the # of days between.

TIMESTAMP

The TIMESTAMP type contains a year, month, day, hour, minute, second, and microsecond. This is the type that I most often use.

Ultimate Resource List

CLI Tools
GUI Tools
Web Tools
Systems/Services
Networks
Containers/Orchestration
Manuals/Howtos/Tutorials

fetch_ghstars.py: quick CLI script to fetch and collate from Github API all of a user's starred repos

Requires Python 3.6+
Creates a subdir 'ghstars-USERNAME' at the current working directory
the raw JSON of each page request is saved as: 01.json, 02.json 0n.json
A flattened, filtered CSV is also created: wrangled.csv

Example usage:

1. switch nginx image to openresty/openresty

2. add the following to server/location (/etc/nginx/conf.d/default.conf)

   set $req_header "";
   set $resp_header "";
   header_filter_by_lua_block{ 
      local h = ngx.req.get_headers();
      for k, v in pairs(h) do
         ngx.var.req_header = ngx.var.req_header .. k.."="..v.." ";

	"""
	The most atomic way to train and run inference for a GPT in pure, dependency-free Python.
	This file is the complete algorithm.
	Everything else is just efficiency.

	@karpathy
	"""

	import os # os.path.exists
	import math # math.log, math.exp

	#!/bin/bash
	# Script to update a firewall rule in a Hetzner Firewall with your current IP address.
	# Good if you would like to restrict SSH access only for your current IP address (secure).

	#################
	# WARNING: This script will overwrite all rules in the firewall rules, so make sure you
	# added all the required rules.
	# I use a separate firewall rule just for SSH access.
	#################

	# copy of https://github.com/ZoeyVid/nginx-quic/blob/latest/Dockerfile
	# syntax=docker/dockerfile:labs
	FROM alpine:3.20.3 AS build
	SHELL ["/bin/ash", "-eo", "pipefail", "-c"]

	ARG LUAJIT_INC=/usr/include/luajit-2.1
	ARG LUAJIT_LIB=/usr/lib

	ARG NGINX_VER=release-1.27.4
	ARG OPENSSL_VER=openssl-3.1.7+quic

	#!/bin/sh

	print_usage() {
	echo "usage: compress_video <input_file>"
	echo "supported formats: mp4, webm, mkv, mov, avi, flv"
	}

	get_extension() {
	f="${1##*/}"
	case "$f" in

	FROM openresty/openresty:1.21.4.1-1-alpine

	ENV PATH=$PATH:/usr/local/openresty/luajit/bin:/usr/local/openresty/nginx/sbin:/usr/local/openresty/bin

	RUN apk update \
	&& apk add curl perl \
	# install nginx-lua-openresty https://opm.openresty.org/package/knyar/nginx-lua-prometheus/
	&& opm get knyar/nginx-lua-prometheus \
	&& mkdir -p /var/log/nginx \
	&& mkdir /var/www \

	import ipaddress

	import requests
	import pandas as pd

	def bot_ip_addresses():
	bots_urls = {
	'google': 'https://developers.google.com/search/apis/ipranges/googlebot.json',
	'bing': 'https://www.bing.com/toolbox/bingbot.json'
	}