Merge pull request #685 from dbt-msft/feat/default-schema-concat-flag

✨ feat: add default schema concatenation flag support and update documentation

Author: axellpadilla

README.md

@@ -68,11 +68,13 @@ See [the changelog](CHANGELOG.md)
   **Example usage in `dbt_project.yml`:**
 
   ```yaml
-  vars:
+  flags:
     dbt_sqlserver_use_default_schema_concat: true  # Enable standard schema concatenation
   ```
 
-  > **Note:** If you want to permanently customise schema generation and avoid any future deprecation of this flag, override the `sqlserver__generate_schema_name` macro directly in your project.
+  This adapter also supports the same setting via `vars:` for backwards compatibility, so either method works in the current release.
+
+  > **Note:** If you want to permanently customise schema generation and avoid any future changes, override the `sqlserver__generate_schema_name` macro directly in your project instead.
 
 
 

dbt/include/sqlserver/macros/adapters/schema.sql

@@ -48,16 +48,19 @@
       - `target.schema`              when no custom schema is set
       - `custom_schema_name` (trim)  when a custom schema is set
 
-    When the `dbt_sqlserver_use_default_schema_concat` variable is set to true,
+    When the `dbt_sqlserver_use_default_schema_concat` flag is enabled,
     this delegates to dbt-core's `default__generate_schema_name`, which concatenates
     `target.schema` + `_` + `custom_schema_name`.
 
-    Set the flag in dbt_project.yml:
-      vars:
+    Set the flag in `dbt_project.yml`:
+      flags:
         dbt_sqlserver_use_default_schema_concat: true
+
 #}
 {% macro sqlserver__generate_schema_name(custom_schema_name, node) -%}
-    {%- if var('dbt_sqlserver_use_default_schema_concat', false) -%}
+    {%- if adapter.behavior.dbt_sqlserver_use_default_schema_concat -%}
+        {{ default__generate_schema_name(custom_schema_name, node) }}
+    {%- elif var('dbt_sqlserver_use_default_schema_concat', false) -%}
         {{ default__generate_schema_name(custom_schema_name, node) }}
     {%- else -%}
         {%- set default_schema = target.schema -%}

tests/unit/adapters/mssql/test_generate_schema_name.py

@@ -27,7 +27,9 @@
 
 _SQLSERVER_GENERATE_SCHEMA_NAME = """
 {% macro sqlserver__generate_schema_name(custom_schema_name, node) -%}
-    {%- if var('dbt_sqlserver_use_default_schema_concat', false) -%}
+    {%- if adapter.behavior.dbt_sqlserver_use_default_schema_concat -%}
+        {{ default__generate_schema_name(custom_schema_name, node) }}
+    {%- elif var('dbt_sqlserver_use_default_schema_concat', false) -%}
         {{ default__generate_schema_name(custom_schema_name, node) }}
     {%- else -%}
         {%- set default_schema = target.schema -%}
@@ -41,8 +43,29 @@
 """
 
 
-def _render(custom_schema_name, target_schema="my_target_schema", use_default_concat=False):
+def _render(
+    custom_schema_name,
+    target_schema="my_target_schema",
+    use_default_concat=False,
+    use_legacy_var=False,
+):
     """Render sqlserver__generate_schema_name with a minimal Jinja2 env."""
+
+    class BehaviorFlag:
+        def __init__(self, enabled):
+            self.enabled = enabled
+
+        def __bool__(self):
+            return self.enabled
+
+        @property
+        def no_warn(self):
+            return self.enabled
+
+    class Behavior:
+        def __init__(self, enabled):
+            self.dbt_sqlserver_use_default_schema_concat = BehaviorFlag(enabled)
+
     env = jinja2.Environment(
         trim_blocks=True,
         lstrip_blocks=True,
@@ -61,10 +84,12 @@ def _render(custom_schema_name, target_schema="my_target_schema", use_default_co
         "node": None,
         "target": type("Target", (), {"schema": target_schema})(),
         "var": lambda key, default=None: (
-            use_default_concat if key == "dbt_sqlserver_use_default_schema_concat" else default
+            use_legacy_var if key == "dbt_sqlserver_use_default_schema_concat" else default
         ),
+        "adapter": type("Adapter", (), {"behavior": Behavior(use_default_concat)})(),
     }
-    return tmpl.render(**ctx).strip()
+    result = tmpl.render(**ctx).strip()
+    return result
 
 
 # ---------------------------------------------------------------------------
@@ -96,23 +121,18 @@ def test_custom_schema_whitespace_is_trimmed(self):
 
     def test_flag_absent_defaults_to_legacy(self):
         """var() returning its default (False) gives the same legacy result."""
-        env = jinja2.Environment(
-            trim_blocks=True, lstrip_blocks=True, extensions=["jinja2.ext.do"]
-        )
-        tmpl = env.from_string(
-            _DEFAULT_GENERATE_SCHEMA_NAME
-            + "\n"
-            + _SQLSERVER_GENERATE_SCHEMA_NAME
-            + "\n"
-            + "{{ sqlserver__generate_schema_name(custom_schema_name, node) }}"
+        assert _render("sales", target_schema="prod", use_default_concat=False) == "sales"
+
+    def test_vars_enable_default_concat_when_flag_absent(self):
+        assert (
+            _render(
+                "reporting",
+                target_schema="dbt_dev",
+                use_default_concat=False,
+                use_legacy_var=True,
+            )
+            == "dbt_dev_reporting"
         )
-        result = tmpl.render(
-            custom_schema_name="sales",
-            node=None,
-            target=type("Target", (), {"schema": "prod"})(),
-            var=lambda key, default=None: default,  # always returns the default (False)
-        ).strip()
-        assert result == "sales"
 
 
 # ---------------------------------------------------------------------------
@@ -165,5 +185,4 @@ def test_custom_schema_concatenation_uses_underscore_separator(self):
     ],
 )
 def test_schema_name_generation(custom_schema_name, target_schema, use_default_concat, expected):
-    result = _render(custom_schema_name, target_schema, use_default_concat)
-    assert result == expected
+    assert _render(custom_schema_name, target_schema, use_default_concat) == expected