Getting Started with SQL

This tutorial shows how to use GraphQLite directly from the SQLite command line.

Prerequisites

  • SQLite3 CLI installed
  • GraphQLite extension built (make extension)

Step 1: Load the Extension

sqlite3 my_graph.db

.load build/graphqlite.dylib
-- On Linux: .load build/graphqlite.so
-- On Windows: .load build/graphqlite.dll

Step 2: Create Nodes

-- Create people
SELECT cypher('CREATE (a:Person {name: "Alice", age: 30})');
SELECT cypher('CREATE (b:Person {name: "Bob", age: 25})');
SELECT cypher('CREATE (c:Person {name: "Charlie", age: 35})');

Step 3: Create Relationships

-- Alice knows Bob
SELECT cypher('
    MATCH (a:Person {name: "Alice"}), (b:Person {name: "Bob"})
    CREATE (a)-[:KNOWS]->(b)
');

-- Bob knows Charlie
SELECT cypher('
    MATCH (b:Person {name: "Bob"}), (c:Person {name: "Charlie"})
    CREATE (b)-[:KNOWS]->(c)
');

Step 4: Query the Graph

-- Find all people
SELECT cypher('MATCH (p:Person) RETURN p.name, p.age');

-- Find relationships
SELECT cypher('MATCH (a:Person)-[:KNOWS]->(b:Person) RETURN a.name, b.name');

-- Friends of friends
SELECT cypher('
    MATCH (a:Person {name: "Alice"})-[:KNOWS]->()-[:KNOWS]->(fof)
    RETURN fof.name
');

Step 5: Using Parameters

-- Safer queries with parameters
SELECT cypher(
    'MATCH (p:Person {name: $name}) RETURN p.age',
    '{"name": "Alice"}'
);

Complete Example

Save this as getting_started.sql:

.load build/graphqlite.dylib

-- Create nodes
SELECT cypher('CREATE (a:Person {name: "Alice", age: 30})');
SELECT cypher('CREATE (b:Person {name: "Bob", age: 25})');
SELECT cypher('CREATE (c:Person {name: "Charlie", age: 35})');

-- Create relationships
SELECT cypher('
    MATCH (a:Person {name: "Alice"}), (b:Person {name: "Bob"})
    CREATE (a)-[:KNOWS]->(b)
');
SELECT cypher('
    MATCH (b:Person {name: "Bob"}), (c:Person {name: "Charlie"})
    CREATE (b)-[:KNOWS]->(c)
');

-- Query
SELECT 'All people:';
SELECT cypher('MATCH (p:Person) RETURN p.name, p.age');

SELECT '';
SELECT 'Who knows who:';
SELECT cypher('MATCH (a:Person)-[:KNOWS]->(b:Person) RETURN a.name, b.name');

SELECT '';
SELECT 'Friends of friends:';
SELECT cypher('
    MATCH (a:Person {name: "Alice"})-[:KNOWS]->()-[:KNOWS]->(fof)
    RETURN fof.name
');

Run it:

sqlite3 < getting_started.sql

Next Steps