Hacktoberfest 2026: die Issues, die Maintainer für den Oktober markiert haben – offen und einsteigerfreundlich. Hacktoberfest-Issues durchsuchen

Error when selecting data from table with JSON datatype

Offen
  • Stimmt etwas nicht?
#261 2 Kommentare 1 Reaktion 1 zugewiesene Person Auf GitHub ansehen

Maintainer antworten meist innerhalb von 1 Tag

@gargsaumya arbeitet bereits daran.

Seit 26.9.2025.

Bewertung

Dieses Issue wurde noch nicht bewertet.

Beschreibung

area: data-types triage done
Describe the bug

When calling cursor.execute to select a json column from a table you receive a runtime error RuntimeError: [Microsoft][ODBC Driver 18 for SQL Server]The connection is no longer usable because the server response for a previously executed statement was incorrectly formatted.

If you are seeing an exception, include the full exceptions details (message and stack trace).

---------------------------------------------------------------------------
RuntimeError                              Traceback (most recent call last)
Cell In[13], [line 1](vscode-notebook-cell:?execution_count=13&line=1)
----> [1](vscode-notebook-cell:?execution_count=13&line=1) with connect(getenv("SQL_CONNECTION_STRING")) as conn: # type: ignore
      2     with conn.cursor() as cursor:
      3         cursor.execute("select * from SalesLT.CustomerJson")

File c:\python\notebook\.venv\Lib\site-packages\mssql_python\connection.py:1028, in Connection.__exit__(self, *args)
   1021 """
   1022 Exit the context manager.
   1023 
   1024 Closes the connection when exiting the context, ensuring proper resource cleanup.
   1025 This follows the modern standard used by most database libraries.
   1026 """
   1027 if not self._closed:
-> [1028](file:///C:/python/notebook/.venv/Lib/site-packages/mssql_python/connection.py:1028)     self.close()

File c:\python\notebook\.venv\Lib\site-packages\mssql_python\connection.py:971, in Connection.close(self)
    966 if not self.autocommit:
    967     # If autocommit is disabled, rollback any uncommitted changes
    968     # This is important to ensure no partial transactions remain
    969     # For autocommit True, this is not necessary as each statement is committed immediately
    970     log('info', "Rolling back uncommitted changes before closing connection.")
--> [971](file:///C:/python/notebook/.venv/Lib/site-packages/mssql_python/connection.py:971)     self._conn.rollback()
    972 # TODO: Check potential race conditions in case of multithreaded scenarios
    973 # Close the connection
    974 self._conn.close()

RuntimeError: [Microsoft][ODBC Driver 18 for SQL Server]The connection is no longer usable because the server response for a previously executed statement was incorrectly formatted.
To reproduce

Include a complete code listing (or project/solution) that we can run to reproduce the issue.

Partial code listings, or multiple fragments of code, will slow down our response or cause us to push the issue back to you to provide code to reproduce the issue.

Run the following tsql in a database with the AdventureWorksLT sample data loaded.

select *
from (SELECT * 
  FROM [SalesLT].[Customer]
  for json AUTO) dt

  create table SalesLT.CustomerJson
    (
        CustomerID int primary key,
        CustomerJson JSON
    )

    insert into SalesLT.CustomerJson (CustomerID, CustomerJson)
    select 1, (SELECT * 
      FROM [SalesLT].[Customer]
      for json AUTO)

with connect(getenv("SQL_CONNECTION_STRING")) as conn: # type: ignore
    with conn.cursor() as cursor:
        cursor.execute("select * from SalesLT.CustomerJson")
        if cursor:
            row = cursor.fetchone()
            if row:
                print(row.CustomerJson)
Expected behavior

A string is returned that is in JSON or convertible to JSON.

Further technical details

Python version: 3.12
SQL Server version: SQL database in Fabric
Operating system: uv

Additional context
Can share uv folder directly since it includes connection strings.

Vorherrschende Sprache
Python
Sterne
478
Forks
62
Ø Merge
3 T. 1 Std.
Gemergte PRs (30 T.)
27

Entwicklungsumgebung

In Codespaces öffnen

Startet den Dev-Container des Projekts im Browser, mit Ihrem eigenen GitHub-Konto.

Erste Schritte

  1. Lesen Sie das ganze Issue und danach den Beitragsleitfaden des Projekts.
  2. Schreiben Sie ins Issue, dass Sie es übernehmen — das erspart doppelte Arbeit.
  3. Forken Sie das Repository und arbeiten Sie in einem Branch.
  4. Öffnen Sie einen Pull Request, der die Issue-Nummer nennt.

Mehr aus microsoft/mssql-python

Alle Issues in microsoft/mssql-python

Ähnliche Issues

Weitere Issues zu Python

Neue Issues direkt in Ihr Postfach

Eine kurze Übersicht über anfängerfreundliche GitHub-Issues.