Qlik Stitch MySQL Extraction Error-“Streaming Result Set Is Still Active”

[Mohammed_Messaoudi]

When replicating data from MySQL integration, users may encounter the following extraction error:

Fatal Error Occurred - Streaming result set com.mysql.cj.protocol.a.result.ResultsetRowsStreaming@xxxx is still active. No statements may be issued when any streaming result sets are open and in use on a given connection. Ensure that you have called .close() on any active streaming result sets before attempting more queries.

Resolution

1. Review the extraction logs and what is occurring just before the error, usually you will find the last query Stitch issued before erroring, for example,
   

   2025-09-30 20:30:00,000Z    tap - INFO  [main] tap-hp-mysql.sync-strategies.common - Querying: SELECT `pk_col`, `col1`, `col2`, `col3` FROM `schema`.`table` WHERE ((`pk_col` > ? OR `pk_col` IS NULL)) AND ((`pk_col` <= ?)) ORDER BY `pk_col` (<last PK value checked>, <max PK value>) 
   2025-09-30 20:32:00,000Z    tap - FATAL [main] tap-hp-mysql.main - Fatal Error Occurred - Streaming result set com.mysql.cj.protocol.a.result.ResultsetRowsStreaming@XXXX is still active. No statements may be issued when any streaming result sets are open and in use on a given connection. Ensure that you have called .close() on any active streaming result sets before attempting more queries.

2. Note the time difference between when the query was issued and when the error occurred, this can help isolate what the timeout value is (for example, 2 minutes) which can then help determine what timeout parameter is being exceeded.
3. You can isolate the impacted table(s) by de-selecting the recently errored table from replication to determine if the issue is with one table or multiple.
4. Run the query from the extraction logs directly in your source database and observe how long it takes to run and complete, assuming it completes. 
   • If it does not complete, you know that the timeout is in your database itself. If it does complete, it is likely due to a network setting in your SSH host.
   • If the query runs long in the source, you should reach out to your DBA team to make sure it is indexed.
     Example of query syntax to run in the source

     SELECT `pk_col`, `col1`, `col2`, `col3`
     FROM `schema`.`table`
     WHERE (`pk_col` IS NULL OR `pk_col` > [last PK value checked])
       AND `pk_col` <= [max PK value]
     ORDER BY `pk_col`;

   • If the query completes within a reasonable time in the source database, do the following: 
     1. Prepare the following queries in your database:

        SHOW FULL PROCESSLIST;
        SELECT ID, USER, HOST, DB, COMMAND, TIME, STATE, INFO 
        FROM information_schema.PROCESSLIST 
        WHERE STATE = 'Sending data';

     2. Manually start an extraction in the Stitch UI
     3. As the extraction is running, execute those queries and capture the results
     4. Note the status of the process owned by the Stitch user and which query it is executing - if it is sleeping, you can considering killing the process(es)
5. Consult with your DBA team to increase the net_read_timeout and net_write_timeout parameters in your MySQL configuration, for reference: Server System Variables | dev.mysql.com/

If you are unable to alleviate the error following the above, please reach out to Qlik Support.

Cause

This error occurs when Stitch has an active server-side streaming ResultSet on a MySQL connection and tries to execute another statement on that same connection before the stream is fully consumed and closed. MySQL’s JDBC driver allows only one active statement per connection while a streaming result is open.

Potential Contributors

• Especially large source tables (for example, wide rows, JSON columns)
• Long-running queries (due to size or volume of tables)
• Slow networks or strict timeout settings (for example, connecting via SSH)

Environment

Stitch