Welcome to Emerald Elephants. The goal of this blog is to demystify some of the workings of the Evergreen ILS database which runs on PostgreSQL. Where does the name come from? Evergreen = Emerald, Postgres’ mascot is an Elephant. No, I don’t think I’m clever but I’m a sucker for allieration. After a few years of teaching SQL for librarians classes and periodically getting questions about some of the corners of the Evergreen database I thought, why answer questions individually when I can compile them for posterity and force Github’s corporate owners to pay one hundreth of a penny hosting some more of my text. Any samples mentioned here will be marked in the appropriate place in the accompanying Github repo @ https://github.com/roganhamby/emeraldelephant.git whose docs/ folder also contains this blog in markdown. But, that’s enough recursion for now.

Feel free to contact me on Twitter @roganhamby or file a request through Github issues.

For those looking for other Evergreen resources:

• Evergreen WIKI
• Jane Sandberg’s posts on Evergreen

Quick links for posts:

• Grokking the Relationship Between Transactions and Bills 2020-06-15
• Paying Off Bills part 1: The Where of It 2020-06-30
• Paying Off Bills part 2: The How of It 2020-07-12
• Ancestors and Descendants 2020-08-01
• Views and Tables in A Materialized World 2020-10-06
• Do the Bibs Match the Copies 2020-10-09
• Circulation Basics, Action.Circulation 2020-10-19
• Circulation Basics, Tables and Views 2020-10-25
• Circulation Basics, Reports 2020-11-30
• Asking Discrete Questions 1 of 2 2020-12-28
• Asking Discrete Questions 2 of 2 2020-12-31
• XMLStarlet - Get It Over With 2021-03-14
• So What? - A Simple Script 2022-10-06
• Load CSV Fast and Easy 2022-10-06
• What is Where in the Database? 2023-03-25