1. Apprendre
    2. /
  2. Cours
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  3. Introduction to Redshift
  • 1

    Redshift, a data warehouse

    Gratuit

    Meet Redshift, a robust columnar data warehouse. We'll explore how columnar and typical data warehouses differ, what makes Redshift unique, how it fits into the AWS and data warehouse ecosystems, and what data types it supports.

  • 2

    SQL on Redshift

    Let's learn about some nuances with Redshift SQL syntax, a close cousin of PostgreSQL's syntax. We compare CTEs and subqueries before moving into mastering date and time, exploring window queries, and wrapping up learning how transactions affect some functions.

  • 3

    Tables and working with semi-structured data

    We'll explore how to create tables, the impact DISTKEY and SORTKEYs have on performance, external schemas/tables with Spectrum and wrap up with handling semi-structured data like JSON with Redshift.

  • 4

    Optimization and Security

    It is time to peak into the world of writing optimized queries and tools available to help optimize. Then, we turn our attention to Redshift security capabilities and how they can impact query output.

Initializing

Exercice

Comparing periods with lag

The Idaho field office wants to see how many tests are performed in each test period (year and month) that it is selected, and compare it with the prior one. They'd like to start with test site 13903 in Minidoka county.

Instructions

100 XP
  • Build a CTE, minidoka_13903, selecting all the columns from idaho_sample and converting the sample_date to a date as an additional column (date_sampled) for station 13903.
  • In the main query:
    • Count the records for the current month
    • Count the records for the prior month via a window function.