"found" by the @discordapp troops the hard way: https://status.discordapp.com/incidents/62gt9cgjwdgf
pinging @zorkian who pointed it out to me.

trivial to repro, this is against a 3.3.13 on fedora-31.

$ etcdctl set /baa schnorp
$ etcdctl get /baa
schnorp
$ echo -ne 'PUT /v2/keys/baa HTTP/1.1\r\nHost: boo\r\nContent-Length: 123\r\n\r\n' | nc localhost 2379
HTTP/1.1 200 OK
...
$ et

From cockroachdb/cockroach#65045 (comment):

TestRingBuffer - 55.76s

We should investigate why it is so and make it faster. Also see #63388 - hopefully we can revert that change too.

Backgroud

After PR #10377 was merged, the explain statement of PG and MySQL has been fully supported. In order to ensure the correctness of the parsing result, we need to implement the logic in ExplainStatementAssert.

Through this issue, you can learn more about how a SQL is parsed and how to verify the parsing result of a SQL in Apache ShardingSphere.

How to solve this issue

Fir

fdbcli flags currently contain a mixture of _ and - (probably for historic reasons). I would propose to unify the flags and only use either _ or - personally I tend to hyphens like recommended in the POSXI standard (https://www.gnu.org/software/libc/manual/html_node/Argument-Syntax.html). Current fdbcli help output:

FoundationDB CLI 6.2 (v6.2.29)
usage: /usr/bin/fdb/6.2/fdbcli

Hello Philip!
I think there is an issue with this part of the code of rqlite (store/store.go).

func (s *Store) Database(leader bool) ([]byte, error) {
	if leader && s.raft.State() != raft.Leader {
		return nil, ErrNotLeader
	}
	// Ensure only one snapshot can take place at once, and block all queries.
	s.mu.Lock()
	defer s.mu.Unlock()

	f, err := ioutil.TempFile("", "rqlilte-snap-

Would be nice to have an explicit gauge of how long a server has been up. This would be useful in case of server restarts.

Easiest would be to use our new Lag metric facility, eg: MillisLag and maybe even set it up at server registration, eg: RpcAndWebServerBase::GenerateInstanceID

Currently, there is no authentication in our MongoDB tests.
Setting MONGO_INITDB_ROOT_USERNAME and MONGO_INITDB_ROOT_PASSWORD environment variables enable auth in MongoDB docker. https://hub.docker.com/_/mongo

Use case:
Right now one can only use date_trunc() to easily define time buckets. date_trunc() only supports predefine time intervals like 1 minute, 1 hour, etc. . In time-series use cases it is often necessary to define different time bucket sizes like e.g. '5 minutes' or '20 minutes'

a workaround for this is the - error prone - integer division on the timestamp e.g.

S

Currently we don't have any mechanism to limit the maximum number of clients that could be handled simultaneously.

This feature should be designed properly. Here is some clue: https://redis.io/topics/clients#maximum-number-of-clients

Now that we support more than 1 data type, we should include the values data type in cache nodes. This give us a way of easily identifying what type of data a key points to e.g. string, queue (and more types in the future)

Currently a cache node object consists of a Key, a Value and a TTL. We should also add a field specifying the type of the Value