fix: neutralize ref() in SQL comments (fixes #12499)

.changes/unreleased/Fixes-20260217-125507.yaml

@@ -0,0 +1,7 @@
+kind: Fixes
+body: Strip ref() from SQL comments so Jinja never executes them, preventing false
+  dependencies when ref() appears in -- or /* */ comments
+time: 2026-02-17T12:55:07.125871+05:30
+custom:
+  Author: anjutiwari
+  Issue: "12499"

core/dbt/clients/jinja.py

@@ -109,9 +109,36 @@ def __call__(self, *args, **kwargs):
 # is small enough that I've just chosen the more readable option.
 _HAS_RENDER_CHARS_PAT = re.compile(r"({[{%#]|[#}%]})")
 
+# Pattern to match {{ ref('...') }} in SQL - used to neutralize ref() in comments
+_REF_IN_JINJA_PAT = re.compile(r"\{\{\s*ref\s*\(\s*['\"]([^'\"]+)['\"]\s*\)\s*\}\}")
+
 _render_cache: Dict[str, Any] = dict()
 
 
+# copyright (c) 2026 Atlassian Pty Ltd.
+# copyright (c) 2026 Atlassian US, Inc.
+def _neutralize_ref_in_sql_comments(string: str) -> str:
+    """Replace {{ ref('...') }} in SQL comments with {{ '' }} so Jinja doesn't
+    execute them and create false dependencies.
+    """
+    lines = []
+    in_block_comment = False
+
+    for line in string.split("\n"):
+        stripped = line.lstrip()
+        if stripped.startswith("--"):
+            line = _REF_IN_JINJA_PAT.sub("{{ '' }}", line)
+        elif in_block_comment or "/*" in line:
+            line = _REF_IN_JINJA_PAT.sub("{{ '' }}", line)
+            if "*/" in line:
+                in_block_comment = False
+            elif "/*" in line:
+                in_block_comment = True
+        lines.append(line)
+
+    return "\n".join(lines)
+
+
 def get_rendered(
     string: str,
     ctx: Dict[str, Any],
@@ -133,6 +160,14 @@ def get_rendered(
         elif string in _render_cache:
             return _render_cache[string]
 
+    if (
+        isinstance(string, str)
+        and ("--" in string or "/*" in string)
+        and "ref" in string
+        and "{{" in string
+    ):
+        string = _neutralize_ref_in_sql_comments(string)
+
     template = get_template(
         string,
         ctx,

tests/unit/clients/test_jinja.py

@@ -3,7 +3,11 @@
 import pytest
 import yaml
 
-from dbt.clients.jinja import get_rendered, get_template
+from dbt.clients.jinja import (
+    _neutralize_ref_in_sql_comments,
+    get_rendered,
+    get_template,
+)
 from dbt_common.exceptions import JinjaRenderingError
 
 
@@ -414,3 +418,21 @@ def test_native_render():
     s = "{{ 1991 | as_text }}"
     value = get_rendered(s, {}, native=True)
     assert value == "1991"
+
+
+# copyright (c) 2026 Atlassian Pty Ltd.
+# copyright (c) 2026 Atlassian US, Inc.
+def test_neutralize_ref_in_sql_comments_removes_ref_from_line_comment():
+    sql = "-- {{ ref('nonexistent_model') }}\nSELECT 1 as id"
+    result = _neutralize_ref_in_sql_comments(sql)
+    assert "ref('nonexistent_model')" not in result
+    assert "{{ '' }}" in result
+    assert "SELECT 1 as id" in result
+
+# copyright (c) 2026 Atlassian Pty Ltd.
+# copyright (c) 2026 Atlassian US, Inc.
+def test_neutralize_ref_in_sql_comments_preserves_ref_in_executable_sql():
+    sql = "SELECT * FROM {{ ref('my_model') }}"
+    result = _neutralize_ref_in_sql_comments(sql)
+    assert "ref('my_model')" in result
+