如何为 SQL Server/Linux 堆栈的 python/pyodbc/unixODBC/MS ODBC Driver 11 设置数据库连接超时？

Question

I've been unable to find a documented way to set a timeout for the initial connection that actually works. I'm not asking about a "query timeout", but rather a timeout on an initial connection attempt in the case that the DB server is completely down or unreachable, and there's no response at all. By default, such connections appear to timeout after 255 seconds - is there a way to set a shorter timeout?

Answer 1

https://stackoverflow.com/a/12946908/1552953

This answer refers to being able to set a timeout on the connection:

Timeout

An optional integer query timeout, in seconds. Use zero, the default, to disable.

The timeout is applied to all cursors created by the connection, so it cannot be changed for a given connection.

If a query timeout occurs, the database should raise an OperationalError with SQLSTATE HYT00 or HYT01.

Note: This attribute only affects queries. To set the timeout for the actual connection process, use the timeout keyword of the pyodbc.connect function.

result = None
with pyodbc.connect('DRIVER={SQL Server};SERVER=mydb;DATABASE=solarwinds;Trusted_Connection=True', timeout=1) as cnxn:
    cursor = cnxn.cursor()
    result = cursor.execute(query).fetchall()

So using the above code it didn't timeout within 1 second, or at least it didn't return a result within 1 second. But it did return a result much faster than without a timeout set.

Answer 2

Solved here. https://stackoverflow.com/a/35640876/2906290

I've confirmed it works for pyodbc with MS SQL Server: https://docs.sqlalchemy.org/en/14/core/engines.html#use-the-connect-args-dictionary-parameter