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swagger: "2.0"
info:
  title: Catalogue API version 2
  description: The new generation Catalogue API
  version: "1.0.0"
host: catalogue-api-v2.master.env
schemes:
  - http
produces:
  - application/json

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Different options

1. For very big sets, create a temporary table with an indexed column and do a SELECT with a JOIN.

2. For large sets, use VALUES. It will create a table like structure which can be JOINed with.

catalogue=> explain select productline_id from productline_tsin_product as ptp, (values (1), (7), (9), (4), (123), (1234)) as lookup where ptp.productline_id = lookup.column1;
┌──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
│                                                          QUERY PLAN                                                          │
├──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┤

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from datetime import date, timedelta
from unittest import TestCase
from integration_layer.transformation import Mapping, Transformation


def tomorrow(today: date) -> date:
    return today + timedelta(days=1)


class TestTransformation(TestCase):

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Protected Media in Django

Introduction

Django manages media based on the following definitions:

BASE_DIR = /var/praekelt/telkom-spliceworks/
MEDIA_ROOT = "%s/media/" % BASE_DIR

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#System Design Interview Cheatsheet

Picking the right architecture = Picking the right battles + Managing trade-offs

##Basic Steps

1. Clarify and agree on the scope of the system

• User cases (description of sequences of events that, taken together, lead to a system doing something useful)
  • Who is going to use it?
  • How are they going to use it?

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

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Category trees revisited

Introduction

Category trees are an important classification utility for e-commerce sites. It is allows similar products to be grouped in a single category and related categories to be grouped together, e.g.

Games + Platform + Xbox

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The good stuff

• Aggregate functions
• Function indexes
• Partial indexes
• CTEs (WITH clauses)
• FDW (foreign data wrappers)
• Interesting types
  • Array
• UUID

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#!/bin/bash

# This script is can be used to enable/disable varnish backends associated
# with a specified server. The state of the varnish backends are displayed
# after the changes have been applied.
#
# At the time of writing the varnish backend names are constructed as a
# concatenation of the servername (with hyphens replaced by underscores) and
# the port on which it listens.
#

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#!/bin/bash

#
# Utility to display JSON data in a pretty-printed, syntax highlighted form.
# If the data is not valid JSON, an error will be reported.
#
# An optional filename can be specified, otherwise input is read from stdin.
#

set -o pipefail