In version 8.0.22 we have added a number of important new features. The first
one is that we introduced the capability to create encrypted backups.
This includes capabilities to create encrypted backups, restore encryped
backups and also encrypt backups that was created without encryption.
The second is that we have added support for IPv6 addresses. If it is
necessary to mix IPv4 and IPv6 addresses in a cluster it is important
to be careful and follow a number of rules as documented.
Performance of replication of BLOB columns has been significantly
improved and similarly for SELECT statements using BLOB columns.
This has been achieved through decreasing the amount of round-trips used
to perform operations involving BLOB tables. This significantly decreases
the latency of operations involving BLOBs.
Also in 8.0.21 an important new feature was added that made some
complex queries significantly faster. We added the ability to push
antijoins and semijoin execution down to the NDB data nodes.
One example query of this is Q22 in TPC-H. This query executes
3.5x faster due to this change and there is likely queries that will
benefit even more than this query due to this change.
select
cntrycode,
count(*) as numcust,
sum(c_acctbal) as totacctbal
from
(
select
substr(c_phone from 1 for 2) as cntrycode,
c_acctbal
from
customer
where
substr(c_phone from 1 for 2) in
('13', '31', '23', '29', '30', '18', '17')
and c_acctbal > (
select
avg(c_acctbal)
from
customer
where
c_acctbal > 0.00
and substr(c_phone from 1 for 2) in
('13', '31', '23', '29', '30', '18', '17')
)
and not exists (
select
*
from
orders
where
o_custkey = c_custkey
)
) as custsale
group by
cntrycode
order by
cntrycode;
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