What is the `<<-EOSQL` code block in Bash when running SQL?
<p>I need to execute a bash script containing SQL, so I am using a script to add custom configurations to a Postgres Docker container, according to the docs here:</p>

<p><a href="https://github.com/docker-library/docs/tree/master/postgres#how-to-extend-this-image" rel="noreferrer">https://github.com/docker-library/docs/tree/master/postgres#how-to-extend-this-image</a></p>

<p>But I don't know what <code>EOSQL</code> means. Here is an example of my script taken from the docs above:</p>

<pre><code>#!/bin/bash
set -e

psql -v ON_ERROR_STOP=1 --username "$POSTGRES_USER" &lt;&lt;-EOSQL
    CREATE USER docker;
    CREATE DATABASE docker;
    GRANT ALL PRIVILEGES ON DATABASE docker TO docker;
    CREATE EXTENSION $MY_EXTENSION;
EOSQL
</code></pre>

<p>So, what is EOSQL? I cannot seem to find much information about this command or keyword.</p>