# Which Problems Are Solved
Systems running with PostgreSQL before Zitadel v2.39 are likely to have
a wrong type for the `in_tx_order` column in the `eventstore.event2`
table. The migration at the time used the `event_sequence` as default
value without typecast, which results in a `bigint` type for that
column. However, when creating the table from scratch, we explicitly
specify the type to be `integer`.
Starting from Zitadel v2.67 we use a Pl/PgSQL function to push events.
The function requires the types from `eventstore.events2` to the same as
the `select` destinations used in the function. In the function
`in_tx_order` is also expected to by of `integer` type.
CochroachDB systems are not affected because `bigint` is an alias to the
`int` type. In other words, CockroachDB uses `int8` when specifying type
`int`. Therefore the types already match.
# How the Problems Are Solved
Retrieve the actual column type currently in use. A template is used to
assign the type to the `ordinality` column returned as `in_tx_order`.
# Additional Changes
- Detailed logging on migration failure
# Additional Context
- Closes#9180
---------
Co-authored-by: Silvan <[email protected]>
# Which Problems Are Solved
https://github.com/zitadel/zitadel/pull/9186 introduced the new `push`
sql function for cockroachdb. The function used the wrong database
function to generate the position of the event and would therefore
insert events at a position before events created with an old Zitadel
version.
# How the Problems Are Solved
Instead of `EXTRACT(EPOCH FROM NOW())`, `cluster_logical_timestamp()` is
used to calculate the position of an event.
# Additional Context
- Introduced in https://github.com/zitadel/zitadel/pull/9186
- Affected versions:
https://github.com/zitadel/zitadel/releases/tag/v2.67.3
# Which Problems Are Solved
The performance of the initial push function can further be increased
# How the Problems Are Solved
`eventstore.push`- and `eventstore.commands_to_events`-functions were
rewritten
# Additional Changes
none
# Additional Context
same optimizations as for postgres:
https://github.com/zitadel/zitadel/pull/9092
# Which Problems Are Solved
We were seeing high query costs in a the lateral join executed in the
commands_to_events procedural function in the database. The high cost
resulted in incremental CPU usage as a load test continued and less
req/sec handled, sarting at 836 and ending at 130 req/sec.
# How the Problems Are Solved
1. Set `PARALLEL SAFE`. I noticed that this option defaults to `UNSAFE`.
But it's actually safe if the function doesn't `INSERT`
2. Set the returned `ROWS 10` parameter.
3. Function is re-written in Pl/PgSQL so that we eliminate expensive
joins.
4. Introduced an intermediate state that does `SELECT DISTINCT` for the
aggregate so that we don't have to do an expensive lateral join.
# Additional Changes
Use a `COALESCE` to get the owner from the last event, instead of a
`CASE` switch.
# Additional Context
- Function was introduced in
https://github.com/zitadel/zitadel/pull/8816
- Closes https://github.com/zitadel/zitadel/issues/8352
---------
Co-authored-by: Silvan <[email protected]>
