[Bug]: Current way of detecting a connection in active txn is not robust

[fengttt]

Is there an existing issue for the same bug?

• I have checked the existing issues.

Environment

- Version or commit-id (e.g. v0.1.0 or 8b23a93):
- Hardware parameters:
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Actual Behavior

#10000

The current way of detecting a connection in Txn is not robust. For example, the regular expression wont match something with comment like

begin /* this is my toy txn */;

See the discussion in the PR.

Expected Behavior

The we we detect active transaction is not robust enough. Is there anything more reliable from the protocol level? For example, when we plan to migrate a connection, can we issue a command to server to check if current connection is in transaction?

Assume connection migration is rare, and probably you HAVE TO migrate no matter what (due to CN crash/congestion etc), why don't we just simply abort current transaction and migrate?

Steps to Reproduce

No response

Additional information

No response

[volgariver6]

fixed by #10486

Now proxy gets txn status from OK packet or EOF packet which is received from server.