Add some DB API 2.0 protocols and types (#6643)

Closes: #1037

stdlib/_typeshed/dbapi.pyi

@@ -0,0 +1,36 @@
+# PEP 249 Database API 2.0 Types
+# https://www.python.org/dev/peps/pep-0249/
+
+from collections.abc import Mapping, Sequence
+from typing import Any, Protocol
+
+DBAPITypeCode = Any | None
+# Strictly speaking, this should be a Sequence, but the type system does
+# not support fixed-length sequences.
+DBAPIColumnDescription = tuple[str, DBAPITypeCode, int | None, int | None, int | None, int | None, bool | None]
+
+class DBAPIConnection(Protocol):
+    def close(self) -> object: ...
+    def commit(self) -> object: ...
+    # optional:
+    # def rollback(self) -> Any: ...
+    def cursor(self) -> DBAPICursor: ...
+
+class DBAPICursor(Protocol):
+    @property
+    def description(self) -> Sequence[DBAPIColumnDescription] | None: ...
+    @property
+    def rowcount(self) -> int: ...
+    # optional:
+    # def callproc(self, __procname: str, __parameters: Sequence[Any] = ...) -> Sequence[Any]: ...
+    def close(self) -> object: ...
+    def execute(self, __operation: str, __parameters: Sequence[Any] | Mapping[str, Any] = ...) -> object: ...
+    def executemany(self, __operation: str, __seq_of_parameters: Sequence[Sequence[Any]]) -> object: ...
+    def fetchone(self) -> Sequence[Any] | None: ...
+    def fetchmany(self, __size: int = ...) -> Sequence[Sequence[Any]]: ...
+    def fetchall(self) -> Sequence[Sequence[Any]]: ...
+    # optional:
+    # def nextset(self) -> None | Literal[True]: ...
+    arraysize: int
+    def setinputsizes(self, __sizes: Sequence[DBAPITypeCode | int | None]) -> object: ...
+    def setoutputsize(self, __size: int, __column: int = ...) -> object: ...