Previously, when the operand of id operator was more than
2147483647, it was raising server error. This is because the
maximum permissible PostgreSQL integers value is 2147483647.
This is fixed by raising a BadNarrowOperatorError in case the
id operand is larger than 2147483647.
For endpoints with a type parameter to indicate whether a message is
a direct or stream message, adds support for passing "channel" as a
value for stream messages.
Part of stream to channel rename project.
Calling `.select_related()` with no arguments joins through every
possible table, recursively. In this case, this currently produces a
query which joins through forty-three tables.
This is rather inefficient, particularly for what is a very common
call which should be very fast.
No callsite depends on having prefetched any joined table on the
object; drop all of the joins.
By default, `SELECT FOR UPDATE` will also lock any rows which are
`JOIN`ed into the selected rows; in the case of UserMessage rows, this
can mean arbitrary Message rows.
Since the messages themselves are not being changed, it is not
necessary to lock them -- and doing so may lead to deadlocks, in the
case that the UserMessage row is locked for update before the Message,
and some other request has already taken a read lock on the Message
and is blocked on the UserMessage write lock.
Change `select_for_update_query` to explicitly only lock UserMessage.
roanster007
Mateusz Mandera
Lauryn Menard
Alex Vandiver
Anders Kaseorg