Refactor BaseRelation.create_ephemeral_from to use identifier instead…

… of alias

dbt/adapters/base/relation.py

@@ -1,4 +1,3 @@
-import re
 from collections.abc import Hashable
 from dataclasses import dataclass, field
 from typing import (
@@ -233,18 +232,20 @@ def quoted(self, identifier):
         )
 
     @staticmethod
-    def add_ephemeral_prefix(alias: str):
-        return re.sub(r"\W+", "", f"__dbt__cte__{alias}")
+    def add_ephemeral_prefix(name: str):
+        return f"__dbt__cte__{name}"
 
     @classmethod
     def create_ephemeral_from(
         cls: Type[Self],
         relation_config: RelationConfig,
         limit: Optional[int] = None,
     ) -> Self:
-        # Note that ephemeral models are based on the alias to give the user
-        # more control over the way that the CTE name is constructed
-        identifier = cls.add_ephemeral_prefix(relation_config.alias)
+        # Note that ephemeral models are based on the identifier, which will
+        # point to the model's alias if one exists and otherwise fall back to
+        # the filename. This is intended to give the user more control over
+        # the way that the CTE name is constructed
+        identifier = cls.add_ephemeral_prefix(relation_config.identifier)
         return cls.create(
             type=cls.CTE,
             identifier=identifier,

dbt/adapters/contracts/relation.py

@@ -49,7 +49,6 @@ def __delitem__(self, key): ...
 class RelationConfig(Protocol):
     resource_type: str
     name: str
-    alias: str
     description: str
     database: str
     schema: str

tests/unit/test_relation.py

@@ -3,7 +3,7 @@
 import pytest
 
 from dbt.adapters.base import BaseRelation
-from dbt.adapters.contracts.relation import RelationConfig, RelationType
+from dbt.adapters.contracts.relation import RelationType
 
 
 @pytest.mark.parametrize(
@@ -81,20 +81,14 @@ def test_render_limited(limit, require_alias, expected_result):
     assert str(my_relation) == expected_result
 
 
-@pytest.mark.parametrize(
-    "alias,expected_cte_id",
-    [
-        ("table", "table"),
-        ("test.<>*~!@#$%^&*table", "testtable")
-    ]
-)
-def test_create_ephemeral_from_uses_alias(alias, expected_cte_id):
+def test_create_ephemeral_from_uses_identifier():
     @dataclass
     class Node:
         """Dummy implementation of RelationConfig protocol"""
+
         name: str
-        alias: str
+        identifier: str
 
-    node = Node(name="name should not be used", alias=alias)
+    node = Node(name="name_should_not_be_used", identifier="test")
     ephemeral_relation = BaseRelation.create_ephemeral_from(node)
-    assert str(ephemeral_relation) == f"__dbt__cte__{expected_cte_id}"
+    assert str(ephemeral_relation) == "__dbt__cte__test"