From 6d917d3728a1d7242e77f814a36014dbd5fd7fb8 Mon Sep 17 00:00:00 2001
From: Olivier Grisel <olivier.grisel@ensta.org>
Date: Tue, 7 Feb 2023 14:32:10 +0100
Subject: [PATCH] docs(backends): document default backend configuration

---
 docs/user_guide/configuration.md | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/docs/user_guide/configuration.md b/docs/user_guide/configuration.md
index 7c832f3ffcb2..5666602bada8 100644
--- a/docs/user_guide/configuration.md
+++ b/docs/user_guide/configuration.md
@@ -57,3 +57,25 @@ def cowsay(msg):
 
 ibis.options.verbose_log = cowsay
 ```
+
+## Default backend
+
+`ibis.options.default_backend` controls which backend is used by table
+expressions returned by top-level functions such as `ibis.memtable`,
+`ibis.read_csv` or `ibis.read_parquet`.
+
+By default, it points to an instance of DuckDB backend. Assuming the [backend
+dependencies have been installed](../install.md), it can be updated by passing
+the name of the backend to `ibis.set_backend` as follows:
+
+```python
+import ibis
+
+expr = ibis.memtable({"column": [0, 1, 2, 3, 4]})
+ibis.get_backend(expr)
+# <ibis.backends.duckdb.Backend at 0x12fa0fb50>
+
+ibis.set_backend("sqlite")
+ibis.get_backend(expr)
+# <ibis.backends.sqlite.Backend at 0x158411d10>
+```