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KeyError raised on prepared statement deallocate

See original GitHub issue

Expected behavior

When executing a prepared statement, the statement shall be executed succesfully

Actual behavior

Multipe responses from Trino contain the same deallocate header, although the code only accepts this operation to be executed once.

See https://github.com/trinodb/trino-python-client/blob/f97aea6afb2663f0a29beb6477c18c9d9a88832e/trino/client.py#L610

Steps To Reproduce

I wasn’t able to reproduce this locally, only in CI. So I assume some type of race condition is happening.

Log output

140581443462912: before: {}
140581443462912: after: {"st_ccb622831a2d43dfb03a186180695c1e": "INSERT INTO delta.test16650588382631922575_test_incremental_delete_insert.seed (\"state\", \"county\", \"city\", \"last_visit_date\")\n VALUES \n  ROW (?, ?, ?, ?)\n, ROW (?, ?, ?, ?)\n, ROW (?, ?, ?, ?)\n, ROW (?, ?, ?, ?)\n, ROW (?, ?, ?, ?)\n, ROW (?, ?, ?, ?)\n"}
140581443462912: Deallocating st_ccb622831a2d43dfb03a186180695c1e
140581443462912: before: {"st_ccb622831a2d43dfb03a186180695c1e": "INSERT INTO delta.test16650588382631922575_test_incremental_delete_insert.seed (\"state\", \"county\", \"city\", \"last_visit_date\")\n VALUES \n  ROW (?, ?, ?, ?)\n, ROW (?, ?, ?, ?)\n, ROW (?, ?, ?, ?)\n, ROW (?, ?, ?, ?)\n, ROW (?, ?, ?, ?)\n, ROW (?, ?, ?, ?)\n"}
140581443462912http://localhost:8080/v1/statement/executing/20[2210](https://github.com/mdesmet/dbt-trino/actions/runs/3197070204/jobs/5219814756#step:4:2211)06_122055_01035_2z8ej/ye8e084beb54f7dd32c5b3d682239264dbe6a6262/0 : <trino.client.TrinoRequest object at 0x7fdbd40a4b50> : st_ccb622831a2d43dfb03a186180695c1e
140581443462912http://localhost:8080/v1/statement/executing/20221006_122055_01035_2z8ej/y382a838b78d9dcd5df455e0fd1335d282cd7f1a2/1 : <trino.client.TrinoRequest object at 0x7fdbd40a4b50> : st_ccb622831a2d43dfb03a186180695c1e
Error while running:
insert into delta.test16650588382631922575_test_incremental_delete_insert.seed ("state", "county", "city", "last_visit_date") values
          (?,?,?,?),(?,?,?,?),(?,?,?,?),(?,?,?,?),(?,?,?,?),(?,?,?,?)
'st_ccb622831a2d43dfb03a186180695c1e'

Operating System

Ubuntu

Trino Python client version

0.317.0

Trino Server version

398

Python version

3.10.5

Are you willing to submit PR?

Yes I am willing to submit a PR!

Issue Analytics

State:
Created a year ago
Comments:8 (8 by maintainers)

Top GitHub Comments

1reaction

hashharcommented, Oct 10, 2022

Ah so the JDBC client maintains two sets - one for added and another for deallocated and when making the requests it merges them together. But here in Python client we merge them when processing headers itself (on each next-uri).

So for now we can “fix” the python client by ignoring the deallocation if statement is already removed and follow-up to see if Trino should do things differently or not. If not having two separate sets makes some sense as it’s easier to reason about (and inspect).

0reactions

hashharcommented, Oct 11, 2022

Reopening this to continue discussion.

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