[Adap-207] remove subshell around get show sql with limit predicate

.changes/unreleased/Under the Hood-20240624-231955.yaml

@@ -0,0 +1,7 @@
+kind: Under the Hood
+body: --limit flag no longer subshells the query. This resolves the dbt Cloud experience
+  issue where limit prevents ordering elements..
+time: 2024-06-24T23:19:55.611142-07:00
+custom:
+  Author: versusfacit
+  Issue: "207"

.gitignore

@@ -154,3 +154,6 @@ cython_debug/
 
 # PyCharm
 .idea/
+
+# Vim
+*.swp

dbt-tests-adapter/dbt/tests/adapter/dbt_show/test_dbt_show.py

@@ -1,5 +1,6 @@
 import pytest
 
+from dbt_common.exceptions import DbtRuntimeError
 from dbt.tests.adapter.dbt_show import fixtures
 from dbt.tests.util import run_dbt
 
@@ -47,9 +48,25 @@ def test_sql_header(self, project):
         run_dbt(["show", "--select", "sql_header", "--vars", "timezone: Asia/Kolkata"])
 
 
+class BaseShowDoesNotHandleDoubleLimit:
+    """see issue: https://github.com/dbt-labs/dbt-adapters/issues/207"""
+
+    DATABASE_ERROR_MESSAGE = 'syntax error at or near "limit"'
+
+    def test_double_limit_throws_syntax_error(self, project):
+        with pytest.raises(DbtRuntimeError) as e:
+            run_dbt(["show", "--limit", "1", "--inline", "select 1 limit 1"])
+
+        assert self.DATABASE_ERROR_MESSAGE in str(e)
+
+
 class TestPostgresShowSqlHeader(BaseShowSqlHeader):
     pass
 
 
 class TestPostgresShowLimit(BaseShowLimit):
     pass
+
+
+class TestShowDoesNotHandleDoubleLimit(BaseShowDoesNotHandleDoubleLimit):
+    pass

dbt/include/global_project/macros/adapters/show.sql

@@ -1,22 +1,26 @@
+{#
+    We expect a syntax error if dbt show is invoked both with a --limit flag to show
+    and with a limit predicate embedded in its inline query. No special handling is
+    provided out-of-box.
+#}
 {% macro get_show_sql(compiled_code, sql_header, limit) -%}
-  {%- if sql_header -%}
+  {%- if sql_header is not none -%}
   {{ sql_header }}
-  {%- endif -%}
-  {%- if limit is not none -%}
+  {%- endif %}
   {{ get_limit_subquery_sql(compiled_code, limit) }}
-  {%- else -%}
-  {{ compiled_code }}
-  {%- endif -%}
 {% endmacro %}
 
-{% macro get_limit_subquery_sql(sql, limit) %}
-  {{ adapter.dispatch('get_limit_subquery_sql', 'dbt')(sql, limit) }}
-{% endmacro %}
+{#
+    Not necessarily a true subquery anymore. Now, merely a query subordinate
+    to the calling macro.
+#}
+{%- macro get_limit_subquery_sql(sql, limit) -%}
+  {{ adapter.dispatch('get_limit_sql', 'dbt')(sql, limit) }}
+{%- endmacro -%}
 
-{% macro default__get_limit_subquery_sql(sql, limit) %}
-    select *
-    from (
-        {{ sql }}
-    ) as model_limit_subq
-    limit {{ limit }}
+{% macro default__get_limit_sql(sql, limit) %}
+  {{ compiled_code }}
+  {% if limit is not none %}
+  limit {{ limit }}
+  {%- endif -%}
 {% endmacro %}