Get the count of affected rows

[petr-k]

• asyncpg version: 0.13.0
• PostgreSQL version: 9.6.1
• Python version: 3.6
• Platform: Ubuntu 18.04
• Do you use pgbouncer?: no
• Did you install asyncpg with pip?: yes

Is there a way to get the number of affected rows, e.g. when issuing a DELETE statement? I haven't been able to find that in the API.

[elprans]

Connection.execute() returns the status line which includes the number of affected rows.

[petr-k]

Thanks, sorry I missed that

[sergeyspatar]

Connection.execute() returns the status line which includes the number of affected rows.

@elprans So it's suggested that if a user needs to know the count of affected rows (for example, how many rows COPY inserted), then he/she needs to parse the status line? And it means users should also verify that the status line has expected format. Wouldn't it be better to save the number of affected rows by the last executed statement in the connection object?

[elprans]

save the number of affected rows by the last executed statement in the connection object

We avoid creating side-effect APIs like that. The functions already return the status message. It you find this use case particularly important, we can add a helper function to parse the status message.

[earshinov]

Has anybody found any documentation on the format of these status lines?

[elprans]

https://www.postgresql.org/docs/current/protocol-message-formats.html (look for CommandComplete)