Add typing for io/sql.py

Author: avinashpancham

pandas/io/sql.py

@@ -383,6 +383,8 @@ def read_sql_query(
         Data type for data or columns. E.g. np.float64 or
         {‘a’: np.float64, ‘b’: np.int32, ‘c’: ‘Int64’}
 
+        .. versionadded:: 1.3.0
+
     Returns
     -------
     DataFrame or Iterator[DataFrame]
@@ -609,7 +611,7 @@ def to_sql(
     index: bool = True,
     index_label=None,
     chunksize: Optional[int] = None,
-    dtype=None,
+    dtype: Optional[DtypeArg] = None,
     method: Optional[str] = None,
 ) -> None:
     """
@@ -768,7 +770,7 @@ def __init__(
         index_label=None,
         schema=None,
         keys=None,
-        dtype=None,
+        dtype: Optional[DtypeArg] = None,
     ):
         self.name = name
         self.pd_sql = pandas_sql_engine
@@ -1430,7 +1432,7 @@ def to_sql(
         index_label=None,
         schema=None,
         chunksize=None,
-        dtype=None,
+        dtype: Optional[DtypeArg] = None,
         method=None,
     ):
         """
@@ -1563,7 +1565,7 @@ def _create_sql_schema(
         frame: DataFrame,
         table_name: str,
         keys: Optional[List[str]] = None,
-        dtype: Optional[dict] = None,
+        dtype: Optional[DtypeArg] = None,
         schema: Optional[str] = None,
     ):
         table = SQLTable(
@@ -1895,7 +1897,7 @@ def to_sql(
         index_label=None,
         schema=None,
         chunksize=None,
-        dtype=None,
+        dtype: Optional[DtypeArg] = None,
         method=None,
     ):
         """
@@ -1980,7 +1982,7 @@ def _create_sql_schema(
         frame,
         table_name: str,
         keys=None,
-        dtype=None,
+        dtype: Optional[DtypeArg] = None,
         schema: Optional[str] = None,
     ):
         table = SQLiteTable(
@@ -1996,7 +1998,12 @@ def _create_sql_schema(
 
 
 def get_schema(
-    frame, name: str, keys=None, con=None, dtype=None, schema: Optional[str] = None
+    frame,
+    name: str,
+    keys=None,
+    con=None,
+    dtype: Optional[DtypeArg] = None,
+    schema: Optional[str] = None,
 ):
     """
     Get the SQL db table schema for the given frame.