adding faq

docs/faq.rst

@@ -0,0 +1,284 @@
+.. _faq:
+
+Frequently Asked Questions
+==========================
+
+General
+-------
+
+What is this project?
+~~~~~~~~~~~~~~~~~~~~~~
+
+linkml-store is a data management solution that provides a common interface to multiple backends,
+including DuckDB, MongoDB, Neo4J, and Solr.
+It is designed to make it easier to work with data in different forms (tabular, JSON, columnar, RDF),
+provide expressive validation at scale, and enable the ability to mix and match different backends.
+
+Is this a database engine?
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+No, linkml-store is not a database engine in itself. It is designed to be used *in combination*
+with your favorite database engines.
+
+Do I need to know LinkML to use this?
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+No, you do not need to know LinkML to use linkml-store. In fact you can use linkml-store in
+"YOLO mode" where you don't even specify a schema (a schema will be induced as far as possible).
+
+However, for serious applications we recommend you always provide a LinkML schema for your
+different datasets.
+
+For more information on LinkML, see the `LinkML documentation <https://linkml.io/linkml/>`_.
+
+Can I use the command line?
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Yes, linkml-store provides a command line interface.
+
+See the `Command Line Tutorial <https://linkml.io/linkml-store/tutorials/Command-Line-Tutorial.html>`_ for examples.
+
+All commands can be used via the base ``linkml-store`` command:
+
+.. code-block:: bash
+
+    linkml-store --help
+
+Note some command line options may change in future until this package is 1.0.0
+
+Can I use the Python API?
+~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Yes, linkml-store provides a Python API.
+
+See the `Python Tutorial <https://linkml.io/linkml-store/tutorials/Python-Tutorial.html>`_ for examples.
+
+Example:
+
+.. code-block:: python
+
+    from linkml_store import Client
+
+    client = Client()
+    db = client.attach_database("duckdb")
+    collection = db.attach_collection("my_collection")
+    collection.insert({"name": "Alice", "age": 42})
+    result = collection.find({"name": "Alice"})
+
+
+Can I use a web API?
+~~~~~~~~~~~~~~~~~~~~
+
+Yes, you can stand up a web API.
+
+To start you should first create a config file, e.g. ``db/conf.yaml``:
+
+Then run:
+
+.. code-block:: bash
+
+    export LINKML_STORE_CONFIG=./db/conf.yaml
+    make api
+
+Can I use a web UI?
+~~~~~~~~~~~~~~~~~~~~
+
+We provide a *very rudimentary* web UI. To start you should first create a config file, e.g. ``db/conf.yaml``:
+
+Then run:
+
+.. code-block:: bash
+
+    export LINKML_STORE_CONFIG=./db/conf.yaml
+    make app
+
+
+What is CRUDSI?
+~~~~~~~~~~~~~~~
+
+CRUDSI is our not particularly serious name for the design pattern that linkml-store follows.
+
+Many database engines and database solutions implement a CRUD layer:
+
+* Create
+* Read
+* Update
+* Delete
+
+linkml-store adds two more operations:
+
+* Search
+* Inference
+
+
+Is this an AI/Machine Learning/LLM/Vector database platform?
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+linkml-store is first and foremost a *data management* platform. However,
+we do provide optional integrations to AI and ML tooling. In particular, you can plug and
+play different solutions for implementing search indexes, including LLM textual embeddings.
+
+Additionally, we believe that robust data management using rich and expressive semantic
+schemas (in combination with the database engine of your choice) is the key to
+making data **AI-ready**.
+
+Is linkml-store production ready?
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+linkml-store is currently not as mature as the core LinkML products. Be warned that
+the API and command line options may change. However, things may be moving fast,
+and you are invited to check back in here later!
+
+Are there tutorials?
+~~~~~~~~~~~~~~~~~~~~
+
+See :ref:`tutorials`
+
+Installation
+-------
+
+How do I install linkml-store?
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. code-block:: bash
+
+    pip install "linkml-store[all]"
+
+This installs both necessary and optional dependencies. We recommend this for now.
+
+As a developer, how do I install linkml-store?
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Check out the repo, and like all linkml projects, use Poetry:
+
+.. code-block:: bash
+
+    git clone <URL>
+    cd linkml-store
+    make install
+
+Backend Integrations
+------------
+
+Does linkml-store support DuckDB?
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Yes, linkml-store supports DuckDB as a backend. DuckDB is a modern columnar in-memory database
+
+See the :ref:`tutorial <tutorials>` for examples.
+
+Note that currently for DuckDB we bypass the `standard linkml to SQL to relational mapping <https://linkml.io/linkml/generators/sqltable.html>`_ step,
+and instead use DuckDB more like a data frame store. Nested objects and lists are stored directly
+(using DuckDB's json integrations behind the scenes), rather than fully normalized.
+
+Does linkml-store support MongoDB?
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Yes, linkml-store supports MongoDB as a backend. MongoDB is a popular NoSQL database.
+
+See the `MongoDB how-to guide <https://linkml.io/linkml-store/how-to/Use-MongoDB.html>`_ for examples.
+
+Does linkml-store support Neo4J?
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Yes, linkml-store supports Neo4J as a backend. Neo4J is a popular graph database.
+
+See the `Neo4J how-to guide <https://linkml.io/linkml-store/how-to/Use-Neo4J.html>`_ for examples.
+
+Does linkml-store support Solr?
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Currently we provide only read support for Solr. We are working on write support.
+
+See the `Solr how-to guide <https://linkml.io/linkml-store/how-to/Query-Solr-using-CLI.html>`_ for examples.
+
+Can I use linkml-store with my favorite triplestore?
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Not yet! This is a surprising omission given LinkML's roots in the semantic web community. However,
+this is planned soon, so check back later.
+
+Data model
+----------
+
+What is the data model in linkml-store?
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+linkml-store has a simple data model:
+
+* A :class:`.Client` provides a top-level interface over one or more databases.
+* A :class:`.Database` consists of one or more possibly heterogeneous collections.
+* A :class:`.Collection` is a queryable set of objects of a similar type.
+
+Search
+------
+
+Can I use LLM vector embeddings for search?
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Yes, you can use LLM vector embeddings for search. This is an optional feature.
+
+See `How to use semantic search <https://linkml.io/linkml-store/how-to/Use-Semantic-Search.html>`_ for examples.
+
+Do I need to use an LLM for search
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+No, but currently other options are limited. You can use a naive tripartite index, or if your backend
+supports search out the box (e.g. Solr) then linkml-store should directly wire into this.
+
+Validation
+----------
+
+Does linkml-store provide validation?
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Yes, linkml-store provides expressive validation using the LinkML framework.
+
+Note that currently validation primarily leverages json-schema integrations, but the intent is to
+provide validation integrations directly with underlying backend stores.
+
+Does linkml-store provide referential integrity validation?
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+See `Check Referential Integrity <https://linkml.io/linkml-store/how-to/Check-Referential-Integrity.html>`_ for examples.
+
+Inference
+---------
+
+What is inference in linkml-store?
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+We have a very flexible notion of inference. It can encompass:
+
+* Statistical or Machine Learning (ML) inference, e.g. via supervised learning
+* Ontological inference, e.g. via reasoning over an ontology
+* Rule-based or procedural inference
+* LLM-based inference
+
+How do I do standard ML inference?
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Currently we provide integrations to scikit-learn, but only expose DecisionTree classifiers for now.
+Remember, linkml-store is not a full fledged ML platform; you should use packages like XGBoost, PyTorch,
+or scikit-learn directly for more complex ML tasks.
+
+See `Predict Missing Data <https://linkml.io/linkml-store/how-to/Predict-Missing-Data.html>`_ for examples.
+
+See also the `Command Line Tutorial <https://linkml.io/linkml-store/tutorials/Command-Line-Tutorial.html>`_ for
+a simple example.
+
+How do I do LLM inference?
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+See the `Command Line Tutorial <https://linkml.io/linkml-store/tutorials/Command-Line-Tutorial.html>`_ (see
+the final section) for an example.
+
+How do I do rule-based inference?
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Check back later for tutorials. For now, you can read about:
+
+- the `LinkML expression language <https://linkml.io/linkml/schemas/expression-language.html>`_
+- `Rules in LinkML <https://linkml.io/linkml/schemas/advanced.html#rules>`_
+
+In future we will provide bindings for rule engines, datalog engines, and OWL reasoners.