Improved register_vector for pg8000 [skip ci]

Author: ankane

pgvector/pg8000/register.py

@@ -11,19 +11,19 @@ def register_vector(conn: Connection) -> None:
     if 'vector' not in type_info:
         raise RuntimeError('vector type not found in the database')
 
-    conn.register_out_adapter(Vector, Vector._to_db)
+    conn.register_out_adapter(Vector, lambda v: v.to_text())
     conn.register_in_adapter(type_info['vector'], Vector.from_text)
 
     try:
         import numpy as np
-        conn.register_out_adapter(np.ndarray, Vector._to_db)
+        conn.register_out_adapter(np.ndarray, lambda v: Vector(v).to_text())
     except ImportError:
         pass
 
     if 'halfvec' in type_info:
-        conn.register_out_adapter(HalfVector, HalfVector._to_db)
+        conn.register_out_adapter(HalfVector, lambda v: v.to_text())
         conn.register_in_adapter(type_info['halfvec'], HalfVector.from_text)
 
     if 'sparsevec' in type_info:
-        conn.register_out_adapter(SparseVector, SparseVector._to_db)
+        conn.register_out_adapter(SparseVector, lambda v: v.to_text())
         conn.register_in_adapter(type_info['sparsevec'], SparseVector.from_text)