Empty unit test fixtures (rows: []) emit invalid LIMIT 0 syntax#699
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…698) dbt-core's get_fixture_sql/get_expected_sql hardcode `limit 0` for empty fixture rows, which is not valid T-SQL. These macros are not dispatched, so shadow them in the adapter package and emit `select top 0` instead. get_expected_sql's empty branch builds typed nulls rather than selecting from dbt_internal_unit_test_actual, which is out of scope inside the view created by sqlserver__get_unit_test_sql. Also fix sqlserver__get_columns_in_query for queries starting with a CTE (hit by unit tests with an empty `expect` block): such queries cannot be wrapped in a subquery, so describe their result set via sp_describe_first_result_set instead of executing them. Non-CTE queries keep the existing TOP 0 wrapping. The CTE detection is factored into a shared sqlserver__select_starts_with_cte helper. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
axellpadilla
requested changes
Jun 4, 2026
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Referencing issue dbt-labs/dbt-adapters#2021 |
…erver__ implementations The shadowed public macros (get_fixture_sql, get_expected_sql) are now thin wrappers that delegate to sqlserver__get_fixture_sql / sqlserver__get_expected_sql, which contain the copied/adapted upstream logic with T-SQL-specific changes (select top 0 instead of limit 0). If dbt-core later adds adapter.dispatch for these macros, this adapter can delete the public wrappers and keep the sqlserver__ implementations as the dispatched handlers.
axellpadilla
approved these changes
Jun 14, 2026
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Fixes #698
dbt-core hardcodes
limit 0for empty fixture rows, which is not valid T-SQL. These macros are not dispatched, so shadow them in the adapter package and emitselect top 0instead.Also fix sqlserver__get_columns_in_query for queries starting with a CTE (hit by unit tests with an empty
expectblock): such queries cannot be wrapped in a subquery, so describe their result set via sp_describe_first_result_set instead of executing them. Non-CTE queries keep the existing TOP 0 wrapping. The CTE detection is factored into a shared sqlserver__select_starts_with_cte helper.