start simple examples

examples/simple-ruby/demo.rb

@@ -0,0 +1,36 @@
+require 'sqlite3'
+require 'sqlite_vec'
+
+
+db = SQLite3::Database.new(':memory:')
+db.enable_load_extension(true)
+SqliteVec.load(db)
+db.enable_load_extension(false)
+
+sqlite_version, vec_version = db.execute("select sqlite_version(), vec_version()").first
+puts "sqlite_version=#{sqlite_version}, vec_version=#{vec_version}"
+
+db.execute("CREATE VIRTUAL TABLE vec_items USING vec0(embedding float[8])")
+
+items = [
+  [1, [0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8]],
+  [2, [0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8]]
+]
+db.transaction do
+  items.each do |item|
+    db.execute("INSERT INTO vec_items(rowid, embedding) VALUES (?, ?)", [item[0], item[1].pack("f*")])
+  end
+end
+
+query = [0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8]
+rows = db.execute(<<-SQL, [query.pack("f*")])
+  SELECT
+    rowid,
+    distance
+  FROM vec_items
+  WHERE embedding MATCH ?
+  ORDER BY distance
+  LIMIT 5
+SQL
+
+puts rows