# Perseid

Perseid is a C++ toolkit for extracting and applying PostgreSQL database
schemas, derived from [Pyrseas](https://github.com/perseas/Pyrseas).

It converts a live database schema to YAML, and can apply YAML descriptions
back to a database—enabling version-controlled schema management.

## Quick start


Extract a database schema to YAML
```
dbtoyaml testdb -o schema.yaml
```

Apply a YAML schema to a database
```
yamltodb testdb schema.yaml --update
```

## Features

- **`dbtoyaml`**: Extracts the definition of database tables and other objects
  (metadata) from PostgreSQL into YAML format, suitable for storing in a
  version control repository.
- **`yamltodb`**: Reads a YAML schema specfication and generates or executes
  SQL `CREATE`/`ALTER`/`DROP` statements to modify a target PostgreSQL
  database so that it will match the input.

## Documentation

```{toctree}
:maxdepth: 2
:caption: User Guide

user/overview
user/known-issues
```

```{toctree}
:maxdepth: 1
user/dbtoyaml
user/yamltodb
user/common-options
user/yaml-format
```

```{toctree}
:maxdepth: 2
:caption: Developer Guide

devel/installation
devel/building
devel/testing
```

```{toctree}
:maxdepth: 2
:caption: API Reference

api/index
```