Quote Tableau field refs and raw identifiers

Author: nicosuave

sidemantic/adapters/tableau.py

@@ -97,6 +97,7 @@
 )
 _MID_RE = re.compile(r"\bMID\s*\(", re.IGNORECASE)
 _FIND_RE = re.compile(r"\bFIND\s*\(", re.IGNORECASE)
+_SIMPLE_SQL_IDENTIFIER_RE = re.compile(r"^[A-Za-z_][A-Za-z0-9_]*$")
 
 # Simple function renames (Tableau name -> SQL name)
 _SIMPLE_RENAMES: list[tuple[re.Pattern, str]] = [
@@ -202,7 +203,7 @@ def _replace_func_balanced(text: str, func_re: re.Pattern, template: str) -> str
 
 
 def _replace_field_refs(formula: str) -> str:
-    """Replace [FieldName] references with bare column names, skipping string literals.
+    """Replace [FieldName] references with quoted column names, skipping string literals.
 
     Handles Tableau's qualified names: [table].[column] -> column
     Skips brackets inside string literals (single or double quoted).
@@ -250,7 +251,7 @@ def _replace_field_refs(formula: str) -> str:
             else:
                 i = end + 1
 
-            result.append(field_name)
+            result.append(_quote_identifier_if_needed(_normalize_column_name(field_name)))
             continue
 
         result.append(c)
@@ -333,12 +334,12 @@ def _translate_formula(formula: str | None) -> tuple[str | None, bool]:
     # Strip // comments before translation (they can contain IF/THEN keywords)
     result = _COMMENT_RE.sub("", formula).strip()
 
-    # Replace [Field] references with bare column names (string-literal-aware)
-    result = _replace_field_refs(result)
-
     # Convert Tableau double-quoted string literals to SQL single quotes
     result = _convert_double_quotes(result)
 
+    # Replace [Field] references with quoted column names (string-literal-aware)
+    result = _replace_field_refs(result)
+
     # ZN(x) -> COALESCE(x, 0)
     result = _replace_func_balanced(result, _ZN_RE, "COALESCE({arg}, 0)")
 
@@ -599,6 +600,17 @@ def _quote_sql_identifier(identifier: str) -> str:
     return '"' + identifier.replace('"', '""') + '"'
 
 
+def _quote_identifier_if_needed(identifier: str) -> str:
+    """Quote a raw Tableau field name when it is not a simple SQL identifier."""
+    if identifier.startswith('"') and identifier.endswith('"'):
+        return identifier
+    if _SIMPLE_SQL_IDENTIFIER_RE.match(identifier):
+        return identifier
+    if "." in identifier:
+        return _quote_column_reference(identifier)
+    return _quote_sql_identifier(identifier)
+
+
 def _quote_column_reference(column_name: str) -> str:
     """Quote a possibly-qualified column reference."""
     parts = _strip_brackets(column_name).split(".")
@@ -839,9 +851,8 @@ def _build_dimension(
         dim_type = _DATATYPE_MAP.get(datatype or "", "categorical")
         granularity = _DATATYPE_GRANULARITY.get(datatype or "")
 
-        # Quote names with spaces/special chars so they produce valid SQL
-        if sql is None and (" " in name or "-" in name):
-            sql = f'"{name}"'
+        if sql is None:
+            sql = _quote_identifier_if_needed(name)
 
         return Dimension(
             name=name,
@@ -876,9 +887,8 @@ def _build_metric(
             return Metric(name=name, agg="count", sql=None, label=caption, public=not hidden)
 
         # For metrics without a formula, sql defaults to the column name.
-        # Quote names with spaces/special chars so they produce valid SQL.
         if sql is None and not formula:
-            sql = f'"{name}"' if " " in name or "-" in name else name
+            sql = _quote_identifier_if_needed(name)
 
         if agg_lower in _PASSTHROUGH_AGGS or not is_translatable:
             # Passthrough or untranslatable: make derived metric
@@ -974,9 +984,7 @@ def _import_orphan_metadata_columns(
             agg_lower = aggregation.lower() if aggregation else ""
 
             # Use remote_alias as the SQL expression (actual DB column name)
-            sql = remote_alias or col_name
-            if " " in sql or "-" in sql:
-                sql = f'"{sql}"'
+            sql = _quote_identifier_if_needed(remote_alias or col_name)
 
             # Role inference based on type and aggregation
             is_measure = agg_lower in measure_aggs and local_type in ("real", "integer")
@@ -1451,7 +1459,7 @@ def _parse_groups_as_segments(self, ds_elem: ET.Element) -> list[Segment]:
 
             if members and level_col:
                 quoted_members = ", ".join(f"'{m}'" for m in members)
-                sql = f"{level_col} IN ({quoted_members})"
+                sql = f"{_quote_identifier_if_needed(level_col)} IN ({quoted_members})"
                 segments.append(Segment(name=group_name, sql=sql))
 
         return segments

tests/adapters/tableau/test_formula.py

@@ -175,6 +175,20 @@ def test_qualified_field_ref():
     assert sql == "amount + 1"
 
 
+def test_field_ref_with_spaces_quoted():
+    """Field refs with spaces are quoted as identifiers."""
+    sql, ok = _translate_formula("[Extracts Incremented At]")
+    assert ok
+    assert sql == '"Extracts Incremented At"'
+
+
+def test_parameter_field_ref_with_spaces_quoted():
+    """Qualified field refs keep the leaf name and quote it when needed."""
+    sql, ok = _translate_formula("[Parameters].[Parameter 1]")
+    assert ok
+    assert sql == '"Parameter 1"'
+
+
 def test_countd_nested():
     """COUNTD with nested expression."""
     sql, ok = _translate_formula("COUNTD(IF [status] = 'active' THEN [user_id] END)")
@@ -206,9 +220,11 @@ def test_double_quoted_strings():
     """Double-quoted string literals converted to single quotes."""
     sql, ok = _translate_formula('IF [x] THEN "Selected" ELSE "Not Selected" END')
     assert ok
+    assert "x" in sql
     assert "'Selected'" in sql
     assert "'Not Selected'" in sql
-    assert '"' not in sql
+    assert '"Selected"' not in sql
+    assert '"Not Selected"' not in sql
 
 
 def test_comment_stripped():

tests/adapters/tableau/test_parsing.py

@@ -220,6 +220,18 @@ def test_hidden_fields(adapter):
     assert price.public is True
 
 
+def test_raw_dimension_names_with_special_chars_are_quoted(adapter):
+    """Raw Tableau dimension names fall back to valid quoted SQL identifiers."""
+    dimension = adapter._build_dimension("Country/Region", "string", None, None, False, None)
+    assert dimension.sql == '"Country/Region"'
+
+
+def test_raw_metric_names_with_special_chars_are_quoted(adapter):
+    """Raw Tableau metric names fall back to valid quoted SQL identifiers."""
+    metric = adapter._build_metric("Profit Ratio (%)", "sum", None, None, False, True, None, None)
+    assert metric.sql == '"Profit Ratio (%)"'
+
+
 # =============================================================================
 # MULTI-TABLE JOIN TESTS
 # =============================================================================