transaction: false model/seed hooks are not honored (silently skipped on default path, error on v2/seed/metric_view)

[sd-db]

Describe the bug

A model or seed hook configured with transaction: false (e.g. pre_hook={'sql': '...', 'transaction': false}) is not run the way the user intends on dbt-databricks. The failure mode depends on the materialization path:

• Default path (use_materialization_v2 = false, the default — table / view / incremental): the transaction: false hook is silently skipped. No error, no log line — it simply never executes.
• use_materialization_v2 = true, and seeds, and metric views: the run fails with:

  [NO_ACTIVE_TRANSACTION] There is no active transaction to commit.
  

Default-transaction hooks (transaction: true or unset) work correctly in both cases. The model/seed config itself is parsed correctly — the issue is in how the materializations execute hooks.

Steps To Reproduce

A model with a transaction: false hook is enough. Minimal repro:

-- models/hook_demo.sql
{{ config(
    materialized='table',
    pre_hook=[
        "create table if not exists {{ this.schema }}.hook_audit (marker string)",
        {"sql": "insert into {{ this.schema }}.hook_audit values ('txn_true')",  "transaction": true},
        {"sql": "insert into {{ this.schema }}.hook_audit values ('txn_false')", "transaction": false}
    ]
) }}
select 1 as id

dbt run -s hook_demo
# then inspect:
#   select * from <schema>.hook_audit;

• Default config: dbt run succeeds, but hook_audit contains only txn_true — the txn_false row is missing. The transaction: false hook never ran.
• With flags: {use_materialization_v2: true} in dbt_project.yml (or for a seed / metric view): dbt run fails with [NO_ACTIVE_TRANSACTION] There is no active transaction to commit.

Expected behavior

Because Databricks has no transactions, a model's pre/post hooks should run regardless of their transaction setting — a transaction: false hook should execute exactly once, like a default hook. (This is the stated intent of dbt-databricks's run_pre_hooks / run_post_hooks override, which calls run_hooks for both inside_transaction passes.)

Screenshots and log output

use_materialization_v2 = true (or seed / metric view) path — the run errors on the commit; that dbt-core's run_hooks emits for the outside-transaction pass:

Databricks adapter: Exception while trying to execute query
        commit;
: [NO_ACTIVE_TRANSACTION] There is no active transaction to commit.
  ... com.databricks.sql.transaction.tahoe.DeltaUnsupportedOperationException:
      [NO_ACTIVE_TRANSACTION] There is no active transaction to commit.
  ... com.databricks.sql.transaction.tahoe.commands.CommitTransactionCommand.run(CommitTransactionCommand.scala:76)

Database Error in model hook_demo (models/hook_demo.sql)
  [NO_ACTIVE_TRANSACTION] There is no active transaction to commit.

Default path: no error; the transaction: false insert is simply absent from the generated SQL.

System information

The output of dbt --version:

Core:
  - installed: 1.11.11
Plugins:
  - databricks: 1.12.1
  - spark: 1.10.1

The operating system you're using: macOS (reproduced on a serverless SQL warehouse; the cause is SQL/macro-level, so any Databricks compute is affected)

The output of python --version: Python 3.10.20

Additional context

Root cause (with file references in this repo):

dbt-core's run_hooks(hooks, inside_transaction) splits hooks by their transaction flag (selectattr('transaction', 'equalto', inside_transaction); default True) and, for the inside_transaction=False pass, emits a literal commit; before the first hook. Databricks/Delta has no transactions and rejects a bare commit; ([NO_ACTIVE_TRANSACTION]).

dbt-databricks calls hooks two inconsistent ways:

Materialization	Path	Hook call	transaction: false result
table.sql	v2 (run_pre_hooks/run_post_hooks, lines 17/43)	calls inside_transaction=False pass	error (commit;)
table.sql	v1 (default) run_hooks(pre_hooks) (45/77)	default inside_transaction=True	silently skipped
view.sql	v2 (10/42) / v1 (45/69)	same	error / silent skip
incremental.sql	v2 (30/92) / v1 (102/219)	same	error / silent skip
seeds.sql	v1 (71/74,104/109) & v2 (29/51)	both reach inside_transaction=False	error
metric_view.sql	always run_pre_hooks/run_post_hooks (8/38)	calls inside_transaction=False pass	error

use_materialization_v2 defaults to False (dbt/adapters/databricks/impl.py), so the silent-skip path is the default user experience. The commit; reaches the server as raw SQL via statement → add_query → handle.execute("commit;"), bypassing the adapter's already-no-op commit().

Suggested fix: override the global run_hooks macro in dbt-databricks to run all hooks in a single pass with no transaction split and no commit; preamble (Databricks has no transaction to commit). This is the only single change that covers both failure modes everywhere, since the v1 else branches call run_hooks directly (not the run_pre_hooks/run_post_hooks wrappers). Overriding only the wrappers fixes the error paths but not the v1 silent-skip; a connection-layer commit; no-op fixes the error paths but not the silent-skip. The v1/v2 hook paths should also be unified for consistency.