Integrate/PostgreSQL: Add section with starter tutorial

docs/ingest/etl/index.md

@@ -121,6 +121,10 @@ Use visual data flow and integration frameworks and platforms.
   MySQL and MariaDB are well-known free and open-source relational database management
   systems (RDBMS), available as standalone and managed variants.
 
+- {ref}`postgresql`
+
+  PostgreSQL is the world's most advanced open source relational database.
+
 - {ref}`sql-server`
 
   Microsoft SQL Server Integration Services (SSIS) is a component of the Microsoft SQL
@@ -237,6 +241,7 @@ Load data from datasets and open table formats.
 - {ref}`n8n`
 - {ref}`nifi`
 - {ref}`node-red`
+- {ref}`postgresql`
 - {ref}`risingwave`
 - {ref}`sql-server`
 - {ref}`streamsets`

docs/integrate/index.md

@@ -52,6 +52,7 @@ n8n/index
 nifi/index
 node-red/index
 plotly/index
+postgresql/index
 Power BI <powerbi/index>
 prometheus/index
 pyviz/index

docs/integrate/postgresql/index.md

@@ -0,0 +1,45 @@
+(postgresql)=
+# PostgreSQL
+
+```{div} .float-right
+[![postgresql-logo](https://www.postgresql.org/media/img/about/press/elephant.png){height=60px loading=lazy}][PostgreSQL]
+```
+```{div} .clearfix
+```
+
+:::{rubric} About
+:::
+
+[PostgreSQL] is the world's most advanced open source relational database.
+
+:::{rubric} Synopsis
+:::
+
+```shell
+uvx 'cratedb-toolkit[io-ingestr]' load table \
+  "postgresql://postgres:postgres@localhost:5432/test?table=public.demo" \
+  --cluster-url="crate://crate:crate@localhost:4200/doc/postgresql_demo"
+```
+
+:::{rubric} Learn
+:::
+
+::::{grid}
+
+:::{grid-item-card} Tutorial: Use CrateDB Toolkit
+:link: postgresql-tutorial
+:link-type: ref
+Load data from PostgreSQL into CrateDB using CrateDB Toolkit.
+:::
+
+::::
+
+
+:::{toctree}
+:maxdepth: 1
+:hidden:
+Tutorial <tutorial>
+:::
+
+
+[PostgreSQL]: https://www.postgresql.org/

docs/integrate/postgresql/tutorial.md

@@ -0,0 +1,99 @@
+(postgresql-tutorial)=
+# Load data from PostgreSQL into CrateDB
+
+The tutorial will walk you through starting [PostgreSQL] and CrateDB,
+inserting a record into PostgreSQL, loading data into a CrateDB table,
+and validating that the data has been stored successfully.
+The data transfer is supported by the
+{ref}`CrateDB Toolkit Ingestr I/O <ctk:ingestr>` data pipeline elements.
+
+## Prerequisites
+
+Docker is used for running all components. This approach works consistently
+across Linux, macOS, and Windows. Alternatively, you can use Podman.
+
+Create a shared network.
+```shell
+docker network create cratedb-demo
+```
+
+Start CrateDB.
+```shell
+docker run --rm --name=cratedb --network=cratedb-demo \
+  --publish=4200:4200 --publish=5432:5432 \
+  docker.io/crate -Cdiscovery.type=single-node
+```
+
+Start PostgreSQL.
+```shell
+docker run --rm --name=postgresql --network=cratedb-demo \
+  --publish=6432:5432 --env "POSTGRES_HOST_AUTH_METHOD=trust" \
+  docker.io/postgres postgres -c log_statement=all
+```
+:::{note}
+Because CrateDB is configured to listen on port `5432` with its PostgreSQL
+interface, let's use a different port for PostgreSQL itself.
+:::
+:::{note}
+Using `POSTGRES_HOST_AUTH_METHOD=trust` disables password checks.
+Use it for local demos only.
+:::
+
+Prepare shortcuts for the CrateDB shell, CrateDB Toolkit, and the PostgreSQL client
+programs.
+
+::::{tab-set}
+
+:::{tab-item} Linux and macOS
+To make the settings persistent, add them to your shell profile (`~/.profile`).
+```shell
+alias crash="docker run --rm -it --network=cratedb-demo ghcr.io/crate/cratedb-toolkit crash"
+alias ctk-ingest="docker run --rm -i --network=cratedb-demo ghcr.io/crate/cratedb-toolkit-ingest ctk"
+alias psql="docker run --rm -i --network=cratedb-demo docker.io/postgres psql"
+```
+:::
+:::{tab-item} Windows PowerShell
+To make the settings persistent, add them to your PowerShell profile (`$PROFILE`).
+```powershell
+function crash { docker run --rm -it --network=cratedb-demo ghcr.io/crate/cratedb-toolkit crash @args }
+function ctk-ingest { docker run --rm -i --network=cratedb-demo ghcr.io/crate/cratedb-toolkit-ingest ctk @args }
+function psql { docker run --rm -i --network=cratedb-demo docker.io/postgres psql @args }
+```
+:::
+:::{tab-item} Windows Command
+```shell
+doskey crash=docker run --rm -it --network=cratedb-demo ghcr.io/crate/cratedb-toolkit crash $*
+doskey ctk-ingest=docker run --rm -i --network=cratedb-demo ghcr.io/crate/cratedb-toolkit-ingest ctk $*
+doskey psql=docker run --rm -i --network=cratedb-demo docker.io/postgres psql $*
+```
+:::
+
+::::
+
+## Usage
+
+Write a few sample records to PostgreSQL.
+```shell
+psql "postgresql://postgres:postgres@postgresql:5432/" <<SQL
+CREATE DATABASE test;
+\connect test;
+CREATE TABLE IF NOT EXISTS demo (id BIGINT, data JSONB);
+INSERT INTO demo (id, data) VALUES (1, '{"temperature": 42.84, "humidity": 83.1}');
+INSERT INTO demo (id, data) VALUES (2, '{"temperature": 84.84, "humidity": 56.99}');
+SQL
+```
+
+Invoke the data transfer pipeline.
+```shell
+ctk-ingest load table \
+  "postgresql://postgres:postgres@postgresql:5432/test?table=public.demo" \
+  --cluster-url="crate://crate:crate@cratedb:4200/doc/postgresql_demo"
+```
+
+Inspect data stored in CrateDB.
+```shell
+crash --hosts cratedb -c "SELECT * FROM doc.postgresql_demo"
+```
+
+
+[PostgreSQL]: https://www.postgresql.org/