S01E04

databases/backends/psycopg.py

@@ -3,10 +3,10 @@
 import psycopg
 import psycopg_pool
 from sqlalchemy.engine.interfaces import Dialect
+from sqlalchemy.dialects.postgresql.psycopg import PGDialect_psycopg
 from sqlalchemy.sql import ClauseElement
 
 from databases.backends.common.records import Record, create_column_maps
-from databases.backends.dialects.psycopg import compile_query, get_dialect
 from databases.core import DatabaseURL
 from databases.interfaces import (
     ConnectionBackend,
@@ -29,7 +29,7 @@ def __init__(
     ) -> None:
         self._database_url = DatabaseURL(database_url)
         self._options = options
-        self._dialect = get_dialect()
+        self._dialect = PGDialect_psycopg()
         self._pool = None
 
     async def connect(self) -> None:
@@ -86,7 +86,7 @@ async def fetch_all(self, query: ClauseElement) -> typing.List[RecordInterface]:
         if self._connection is None:
             raise RuntimeError("Connection is not acquired")
 
-        query_str, args, result_columns = compile_query(query, self._dialect)
+        query_str, args, result_columns = self._compile(query)
 
         async with self._connection.cursor() as cursor:
             await cursor.execute(query_str, args)
@@ -99,7 +99,7 @@ async def fetch_one(self, query: ClauseElement) -> typing.Optional[RecordInterfa
         if self._connection is None:
             raise RuntimeError("Connection is not acquired")
 
-        query_str, args, result_columns = compile_query(query, self._dialect)
+        query_str, args, result_columns = self._compile(query)
 
         async with self._connection.cursor() as cursor:
             await cursor.execute(query_str, args)
@@ -125,7 +125,7 @@ async def execute(self, query: ClauseElement) -> typing.Any:
         if self._connection is None:
             raise RuntimeError("Connection is not acquired")
 
-        query_str, args, _ = compile_query(query, self._dialect)
+        query_str, args, _ = self._compile(query)
 
         async with self._connection.cursor() as cursor:
             await cursor.execute(query_str, args)
@@ -141,7 +141,7 @@ async def iterate(
         if self._connection is None:
             raise RuntimeError("Connection is not acquired")
 
-        query_str, args, result_columns = compile_query(query, self._dialect)
+        query_str, args, result_columns = self._compile(query)
         column_maps = create_column_maps(result_columns)
 
         async with self._connection.cursor() as cursor:
@@ -164,6 +164,17 @@ def raw_connection(self) -> typing.Any:
             raise RuntimeError("Connection is not acquired")
         return self._connection
 
+    def _compile(
+        self, query: ClauseElement,
+    ) -> typing.Tuple[str, typing.Mapping[str, typing.Any], tuple]:
+        compiled = query.compile(dialect=self._dialect)
+
+        compiled_query = compiled.string
+        params = compiled.params
+        result_map = compiled._result_columns
+
+        return compiled_query, params, result_map
+
 
 class PsycopgTransaction(TransactionBackend):
     _connecttion: PsycopgConnection

tests/test_databases.py

@@ -1338,6 +1338,7 @@ async def test_queries_with_expose_backend_connection(database_url):
                     "mysql+asyncmy",
                     "mysql+aiomysql",
                     "postgresql+aiopg",
+                    "postgresql+psycopg",
                 ]:
                     insert_query = "INSERT INTO notes (text, completed) VALUES (%s, %s)"
                 else: