Add vector search example

Author: penberg

examples/vector.py

@@ -0,0 +1,23 @@
+import libsql_experimental as libsql
+
+conn = libsql.connect("vector.db")
+
+conn.execute(
+    "CREATE TABLE movies (title TEXT, year INT, embedding F32_BLOB(3))")
+conn.execute("CREATE INDEX movies_idx ON movies (libsql_vector_idx(embedding))")
+
+conn.execute(""""
+  INSERT INTO movies (title, year, embedding) VALUES
+    ('Napoleon', 2023, vector('[1,2,3]')),
+    ('Black Hawk Down', 2001, vector('[10,11,12]')),
+    ('Gladiator', 2000, vector('[7,8,9]')),
+    ('Blade Runner', 1982, vector('[4,5,6]'));
+""")
+
+cur = conn.execute("""
+  SELECT title, year
+  FROM vector_top_k('movies_idx', '[4,5,6]', 3)
+  JOIN movies ON movies.rowid = id
+""")
+
+print(cur.fetchal())