Adding badges

Author: moufmouf

README.md

@@ -1,3 +1,6 @@
+[![Latest Stable Version](https://poser.pugx.org/mouf/schema-analyzer/v/stable)](https://packagist.org/packages/mouf/schema-analyzer)
+[![Latest Unstable Version](https://poser.pugx.org/mouf/schema-analyzer/v/unstable)](https://packagist.org/packages/mouf/schema-analyzer)
+[![License](https://poser.pugx.org/mouf/schema-analyzer/license)](https://packagist.org/packages/mouf/schema-analyzer)
 [![Scrutinizer Code Quality](https://scrutinizer-ci.com/g/thecodingmachine/schema-analyzer/badges/quality-score.png?b=1.0)](https://scrutinizer-ci.com/g/thecodingmachine/schema-analyzer/?branch=1.0)
 [![Build Status](https://travis-ci.org/thecodingmachine/schema-analyzer.svg?branch=1.0)](https://travis-ci.org/thecodingmachine/schema-analyzer)
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@@ -26,6 +29,41 @@ You can install this package through Composer:
 The packages adheres to the [SemVer](http://semver.org/) specification, and there will be full backward compatibility
 between minor versions.
 
-## Usage
+## Detecting junction tables
 
-Start by instanciating 
+The starting point is always a DBAL Schema. Pass the schema to SchemaAnalyzer, and then, simply call the functions.
+
+```php
+// $conn is the DBAL connection.
+$schema = $conn->getSchemaManager()->createSchema();
+
+// Let's detect all junctions tables
+$tables = $schema->detectJunctionTables();
+// This will return an array of Doctrine\DBAL\Schema\Table objects
+```
+
+A **junction table** is a table:
+
+- that has **exactly 2 foreign keys**
+- that has **only 2 columns** (or **3 columns** if the one of those is an *autoincremented primary key*).
+
+## Computing the shortest path between 2 tables
+
+Following foreign keys, the `getShortestPath` function will try to find the shortest path between 2 tables.
+It will return the list of foreign keys it used to link the 2 tables.
+
+Internals:
+
+- Each foreign key has a *cost* of 1
+- Junction tables have a cost of 1.5, instead of 2 (one for each foreign key)
+
+```php
+// $conn is the DBAL connection.
+$schema = $conn->getSchemaManager()->createSchema();
+
+// Let's detect the shortest path between 2 tables:
+$fks = $schema->getShortestPath("users", "rights");
+// This will return an array of Doctrine\DBAL\Schema\ForeignKeyConstraint objects
+```
+
+// TODO: Ambiguity exception!