peter

-- Order by one indexed column (FAST)
newsdesk_production=# explain analyze select * from pressreleases order by published_at DESC limit 100;
                                                                                   QUERY PLAN                                                                                    
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Limit  (cost=0.00..249.91 rows=100 width=1207) (actual time=26.070..716.453 rows=100 loops=1)
   ->  Index Scan Backward using pressreleases_published_at_index on pressreleases  (cost=0.00..964766.62 rows=386042 width=1207) (actual time=26.067..716.343 rows=100 loops=1)
 Total runtime: 716.709 ms
(3 rows)

- Order by two separately indexed columns (SLOW)

mmrwoods

# dump all databases once every 24 hours
45 4 * * * root nice -n 19 su - postgres -c "pg_dumpall --clean" | gzip -9 > /var/local/backup/postgres/postgres_all.sql.gz

# vacuum all databases every night (full vacuum on Sunday night, lazy vacuum every other night)
45 3 * * 0 root nice -n 19 su - postgres -c "vacuumdb --all --full --analyze"
45 3 * * 1-6 root nice -n 19 su - postgres -c "vacuumdb --all --analyze --quiet"

# re-index all databases once a week
0 3 * * 0 root nice -n 19 su - postgres -c 'psql -t -c "select datname from pg_database order by datname;" | xargs -n 1 -I"{}" -- psql -U postgres {} -c "reindex database {};"'

janlay

package main

import (
	"fmt"
	"math"
)

func Sqrt(x float64) float64 {
	z := 1.0
	for i := 1; i <= 100; i++ {

jsanders

package main

import("fmt"; "math")

func Sqrt(x float64) (z float64) {
  z, delta := 1.0, 1.0

  for delta > 1e-4 {
    z0 := z

tetsuok

package main

import "fmt"

// Very naive answer.
// fibonacci is a function that returns
// a function that returns an int.
func fibonacci() func() int {
	n := 0
	a := 0

earthgecko

#!/bin/bash
# bash generate random alphanumeric string
#

# bash generate random 32 character alphanumeric string (upper and lowercase) and 
NEW_UUID=$(cat /dev/urandom | tr -dc 'a-zA-Z0-9' | fold -w 32 | head -n 1)

# bash generate random 32 character alphanumeric string (lowercase only)
cat /dev/urandom | tr -dc 'a-z0-9' | fold -w 32 | head -n 1

abesto

/*
A Tour of Go: page 44
http://tour.golang.org/#44

Exercise: Loops and Functions

As a simple way to play with functions and loops, implement the square root function using Newton's method.

In this case, Newton's method is to approximate Sqrt(x) by picking a starting point z and then repeating: z - (z*z - x) / (2 * z)

rgreenjr

-- show running queries (pre 9.2)
SELECT procpid, age(clock_timestamp(), query_start), usename, current_query 
FROM pg_stat_activity 
WHERE current_query != '<IDLE>' AND current_query NOT ILIKE '%pg_stat_activity%' 
ORDER BY query_start desc;

-- show running queries (9.2)
SELECT pid, age(clock_timestamp(), query_start), usename, query 
FROM pg_stat_activity 
WHERE query != '<IDLE>' AND query NOT ILIKE '%pg_stat_activity%' 

ryanjbonnell

// Use X-Forwarded-For HTTP Header to Get Visitor's Real IP Address
	
if ( isset( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
	$http_x_headers = explode( ',', $_SERVER['HTTP_X_FORWARDED_FOR'] );

	$_SERVER['REMOTE_ADDR'] = $http_x_headers[0];
}

ibussieres

echo "deb http://apt.postgresql.org/pub/repos/apt/ precise-pgdg main" | sudo tee /etc/apt/sources.list.d/pgdg.list
wget --quiet -O - https://www.postgresql.org/media/keys/ACCC4CF8.asc | sudo apt-key add -
sudo apt-get update
sudo apt-get install postgresql-9.3 postgresql-server-dev-9.3 postgresql-contrib-9.3 -y
 
sudo su - postgres -c "psql template1 -p 5433 -c 'CREATE EXTENSION IF NOT EXISTS hstore;'"
sudo su - postgres -c "psql template1 -p 5433 -c 'CREATE EXTENSION IF NOT EXISTS \"uuid-ossp\";'"
sudo su - postgres -c "service postgresql stop"
sudo su - postgres -c '/usr/lib/postgresql/9.3/bin/pg_upgrade -b /usr/lib/postgresql/9.1/bin -B /usr/lib/postgresql/9.3/bin -d /var/lib/postgresql/9.1/main/ -D /var/lib/postgresql/9.3/main/ -O "-c config_file=/etc/postgresql/9.3/main/postgresql.conf" -o "-c config_file=/etc/postgresql/9.1/main/postgresql.conf"'