Query timeout

[riziles]

This package is absolutely fantastic. Quick question: is there any way to set a query timeout to kill accidental runaways? I believe that the c API supports this with the "SQL_ATTR_QUERY_TIMEOUT" property. Not sure about your Rust API.

https://learn.microsoft.com/en-us/sql/odbc/reference/syntax/sqlsetstmtattr-function?view=sql-server-ver16

[pacman82]

Hello @riziles ,

This package is absolutely fantastic

thanks

Quick question: is there any way to set a query timeout to kill accidental runaways?

Not yet.

I believe that the c API supports this with the "SQL_ATTR_QUERY_TIMEOUT" property.

I think it does. I read the semantics as timeout until select starts. Not necessarily until it retruns. Probably driver specific anyway though.

Not sure about your Rust API.

No, not supported in the rust bindings as of now. For no other reason than, that so far nobody asked for it. Overall I see no roadblocks to put it in there and forward it through the python bindings of arrow-odbc.

Best, Markus

[riziles]

Cool, thank you. I've triggered one too many multi-hour runaway queries in the past 20 years (okay more like 15 or 20 too many).

FYI, here's a simple test I use just to make sure my timeouts are firing when using pyodbc, aioodbc, node-odbc, etc:

import pyodbc

con_str = "\
Driver={ODBC Driver 17 for SQL Server};\
Server=server;\
Database=db;\
Trusted_Connection=Yes;\
"

with pyodbc.connect(
    con_str
) as con:
    con.timeout = 2

    try:
        r = con.execute(
            """
            WAITFOR DELAY '0:0:03';
            select 'Timeout not hit'
            """
        )
        print(r.fetchone())
    except pyodbc.OperationalError as e:
        print(e)

[pacman82]

The following test now passes using arrow-odbc python bindings 8.2.0.

def test_query_timeout():
    """
    """
    # Given a long running query
    long_running_query = "WAITFOR DELAY '0:0:03'; SELECT 42 as a"

    # When setting a query timeout of 1 second and fetching data, then we expect a timeout
    with raises(Error, match="Query timeout expired"):
        _arrow_reader = read_arrow_batches_from_odbc(
            query=long_running_query,
            connection_string=MSSQL,
            query_timeout_sec=1
        )

Enjoy!

[riziles]

Thank you @pacman82 so much!!!!