Conditionally query scylla_tables for table metadata

[ayashjorden]

When using scylladb/gocql with upstream Cassandra, the driver queries system_schema.tables to get
table metadata.
When using scylladb/gocql with ScyllaDB, the
driver should also query system_schema.scylla_tables.

Closes #579

[mykaul]

Typo: Condtionalty in subject.

[Copilot]

Pull Request Overview

This PR conditionally queries the scylla_tables system table only when connected to ScyllaDB, improving compatibility when using the gocql driver with upstream Cassandra. Previously, the driver would always attempt to query both system_schema.tables and system_schema.scylla_tables regardless of the database type.

• Added conditional logic to skip ScyllaDB-specific table queries when connected to Cassandra
• Updated comment to clarify that scylla_tables is only queried for ScyllaDB connections

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[ayashjorden]

@mykaul @dkropachev fixed

[ayashjorden]

@dkropachev any insight on the failed workflow?

EDIT: found it

github.com/gocql/gocql.(*Conn).getScyllaSupported(...)
	/home/runner/work/gocql/gocql/conn.go:260
github.com/gocql/gocql.(*Conn).isScyllaConn(...)
	/home/runner/work/gocql/gocql/scylla.go:286
github.com/gocql/gocql.getTableMetadata(0xc00019e408, {0xa6401d, 0x6})

EDIT#2: How would I reproduce the error? are there changes required elsewhere in the code?

[sylwiaszunejko]

@dkropachev any insight on the failed workflow?

EDIT: found it

github.com/gocql/gocql.(*Conn).getScyllaSupported(...)
	/home/runner/work/gocql/gocql/conn.go:260
github.com/gocql/gocql.(*Conn).isScyllaConn(...)
	/home/runner/work/gocql/gocql/scylla.go:286
github.com/gocql/gocql.getTableMetadata(0xc00019e408, {0xa6401d, 0x6})

EDIT#2: How would I reproduce the error? are there changes required elsewhere in the code?

func (s *Session) getConn() *Conn can return nil, you should check if the connection if not nil before calling isScyllaConn

[ayashjorden]

@dkropachev any insight on the failed workflow?
EDIT: found it

github.com/gocql/gocql.(*Conn).getScyllaSupported(...)
	/home/runner/work/gocql/gocql/conn.go:260
github.com/gocql/gocql.(*Conn).isScyllaConn(...)
	/home/runner/work/gocql/gocql/scylla.go:286
github.com/gocql/gocql.getTableMetadata(0xc00019e408, {0xa6401d, 0x6})

EDIT#2: How would I reproduce the error? are there changes required elsewhere in the code?

func (s *Session) getConn() *Conn can return nil, you should check if the connection if not nil before calling isScyllaConn

Ok, thought there was something else, I'll fix it

[ayashjorden]

Hi @mykaul , wanted to check in on this, since its merged, when is it going to be released?
I assume that scylla/gocqlx would also need to be updated to use the new condition (among other functionalities that were merged.).

[mykaul]

Hi @mykaul , wanted to check in on this, since its merged, when is it going to be released? I assume that scylla/gocqlx would also need to be updated to use the new condition (among other functionalities that were merged.).

I hope soon, since we already have 60 PRs since last release (v1.15.3...master ). I assume we'd want to complete few additional items (#592 for example)

Yes, we always update other projects using our Go driver when we release a new driver.

[dkropachev]

We will release it soon

[dkropachev]

Released at https://github.com/scylladb/gocql/releases/tag/v1.16.0