Sessions and default database support in MySQL wire protocol

[yurriy]

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Category (leave one):

• Improvement

Short description (up to few sentences):
Creating a new session in each MySQL connection. Using default database from config.xml, if it is not specified by client. #5476

[alexey-milovidov]

Great! PS. Did you check (manually) that the user settings (e. g. max_memory_usage specified in users.xml) work?

[yurriy]

Great! PS. Did you check (manually) that the user settings (e. g. max_memory_usage specified in users.xml) work?

No, the last thing to do from #5476 is implementing user settings. I was going to make them separately.

[alexey-milovidov]

If I remember correctly, setUser will be enough?

[yurriy]

If I remember correctly, setUser will be enough?

Also replacing strings by PODArray, which uses MemoryTracker.

[nshah14285]

I have installed clickhouse 19.10.1.688 version. As per project requirement, I have to connect to clickhouse database from MYSQL client, so I tried below command

mysql --protocol tcp -h localhost -P 9000 -u default --password -e "CREATE DATABASE x;"

and

mysql --protocol tcp -h localhost -P 9000 default -u default --password -e "CREATE DATABASE x;"

and also tried to connect from node application but it gets hang and after some time receive below error

653008 [ 41 ] {} ServerErrorHandler: Code: 209, e.displayText() = DB::NetException: Timeout exceeded while reading from socket (127.0.0.1:47000), Stack trace:

Could you please tell how to connect.

Thanks,
Nishit Shah

[yurriy]

I have installed clickhouse 19.10.1.688 version. As per project requirement, I have to connect to clickhouse database from MYSQL client, so I tried below command

mysql --protocol tcp -h localhost -P 9000 -u default --password -e "CREATE DATABASE x;"

and

mysql --protocol tcp -h localhost -P 9000 default -u default --password -e "CREATE DATABASE x;"

and also tried to connect from node application but it gets hang and after some time receive below error

653008 [ 41 ] {} ServerErrorHandler: Code: 209, e.displayText() = DB::NetException: Timeout exceeded while reading from socket (127.0.0.1:47000), Stack trace:

Could you please tell how to connect.

Thanks,
Nishit Shah

Probably you are trying to connect to a native protocol server, which listens 9000 port by default. To be able to connect using mysql, you should add <mysql_port>9004</mysql_port> to config.xml.

[nshah14285]

Thanks.
It's working now.

[nshah14285]

I am able to connect ClickHouse from mysql client but when I tried to connect from node application using MYSQL module it throws an error

max_packet_size: 0
character_set: !
user: default
auth_response length: 20
auth_response: ;t#3
�O1�cf�k�Xkva�
database: test
auth_plugin_name:
2019.06.20 13:32:35.000536 [ 41 ] {} MySQLHandler: DB::Exception: Required capability: CLIENT_PLUGIN_AUTH.

Thanks

[yurriy]

I am able to connect ClickHouse from mysql client but when I tried to connect from node application using MYSQL module it throws an error

MYSQL library does not support authentication plugins other than mysql_native_password, which makes it impossible to use it with ClickHouse now. We will add tests for this client when either this or this is merged.