Fixes SQL syntax errors when using single quotes in validValues or missingValues for Soda quality checks.

CHANGELOG.md

@@ -13,6 +13,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Restrict DuckDB dependency to < 1.4.0 (#972)
 - Fixed schema evolution support for optional fields in CSV and Parquet formats. Optional fields marked with `required: false` are no longer incorrectly treated as required during validation, enabling proper schema evolution where optional fields can be added to contracts without breaking validation of historical data files (#977)
+- Fixed SQL syntax errors when using single quotes in `validValues` or `missingValues` for Soda quality checks. Single quotes are now properly escaped by doubling them (SQL standard) before generating SodaCL YAML
 
 ## [0.11.2] - 2025-12-15
 

datacontract/engines/data_contract_checks.py

@@ -165,7 +165,6 @@ def to_schema_name(schema_object: SchemaObject, server_type: str) -> str:
     return schema_object.name
 
 
-
 def check_property_is_present(model_name, field_name, quoting_config: QuotingConfig = QuotingConfig()) -> Check:
     check_type = "field_is_present"
     check_key = f"{model_name}__{field_name}__{check_type}"
@@ -492,7 +491,9 @@ def check_property_enum(model_name: str, field_name: str, enum: list, quoting_co
     )
 
 
-def check_property_regex(model_name: str, field_name: str, pattern: str, quoting_config: QuotingConfig = QuotingConfig()):
+def check_property_regex(
+    model_name: str, field_name: str, pattern: str, quoting_config: QuotingConfig = QuotingConfig()
+):
     if quoting_config.quote_field_name:
         field_name_for_soda = f'"{field_name}"'
     else:
@@ -661,7 +662,9 @@ def check_property_invalid_values(
     }
 
     if valid_values is not None:
-        sodacl_check_config["valid values"] = valid_values
+        # Escape single quotes for SQL by doubling them
+        escaped_values = [v.replace("'", "''") if isinstance(v, str) else v for v in valid_values]
+        sodacl_check_config["valid values"] = escaped_values
 
     sodacl_check_dict = {
         checks_for(model_name, quoting_config, check_type): [
@@ -706,7 +709,9 @@ def check_property_missing_values(
     if missing_values is not None:
         filtered_missing_values = [v for v in missing_values if v is not None]
         if filtered_missing_values:
-            sodacl_check_config["missing values"] = filtered_missing_values
+            # Escape single quotes for SQL by doubling them
+            escaped_values = [v.replace("'", "''") if isinstance(v, str) else v for v in filtered_missing_values]
+            sodacl_check_config["missing values"] = escaped_values
 
     sodacl_check_dict = {
         checks_for(model_name, quoting_config, check_type): [
@@ -819,7 +824,9 @@ def check_quality_list(
                         )
                     )
                 else:
-                    checks.append(check_property_duplicate_values(schema_name, property_name, threshold, quoting_config))
+                    checks.append(
+                        check_property_duplicate_values(schema_name, property_name, threshold, quoting_config)
+                    )
             elif quality.metric == "nullValues":
                 if property_name is not None:
                     checks.append(check_property_null_values(schema_name, property_name, threshold, quoting_config))
@@ -829,15 +836,19 @@ def check_quality_list(
                 if property_name is not None:
                     valid_values = quality.arguments.get("validValues") if quality.arguments else None
                     checks.append(
-                        check_property_invalid_values(schema_name, property_name, threshold, valid_values, quoting_config)
+                        check_property_invalid_values(
+                            schema_name, property_name, threshold, valid_values, quoting_config
+                        )
                     )
                 else:
                     logger.warning("Quality check invalidValues is only supported at field level")
             elif quality.metric == "missingValues":
                 if property_name is not None:
                     missing_values = quality.arguments.get("missingValues") if quality.arguments else None
                     checks.append(
-                        check_property_missing_values(schema_name, property_name, threshold, missing_values, quoting_config)
+                        check_property_missing_values(
+                            schema_name, property_name, threshold, missing_values, quoting_config
+                        )
                     )
                 else:
                     logger.warning("Quality check missingValues is only supported at field level")
@@ -1125,4 +1136,3 @@ def _parse_iso8601_to_seconds(duration: str) -> int | None:
         return int(match.group(1))
 
     return None
-

tests/test_data_contract_checks.py

@@ -1,6 +1,12 @@
+import yaml
 from open_data_contract_standard.model import DataQuality, Server
 
-from datacontract.engines.data_contract_checks import QuotingConfig, prepare_query
+from datacontract.engines.data_contract_checks import (
+    QuotingConfig,
+    check_property_invalid_values,
+    check_property_missing_values,
+    prepare_query,
+)
 
 
 def test_prepare_query_schema_placeholder():
@@ -71,4 +77,34 @@ def test_prepare_query_all_placeholders_with_dollar():
 
     result = prepare_query(quality, "my_table", "my_field", QuotingConfig(), server)
 
-    assert result == "SELECT my_field FROM my_schema.my_table"
+    assert result == "SELECT my_field FROM my_schema.my_table"
+
+
+def test_check_property_invalid_values_escapes_single_quotes():
+    """Test that single quotes in validValues are properly escaped for SQL."""
+    check = check_property_invalid_values(
+        model_name="test_model",
+        field_name="test_field",
+        threshold="= 0",
+        valid_values=["peter's", "john's"],
+    )
+
+    yaml_dict = yaml.safe_load(check.implementation)
+    valid_values = yaml_dict["checks for test_model"][0]["invalid_count(test_field) = 0"]["valid values"]
+
+    assert valid_values == ["peter''s", "john''s"]
+
+
+def test_check_property_missing_values_escapes_single_quotes():
+    """Test that single quotes in missingValues are properly escaped for SQL."""
+    check = check_property_missing_values(
+        model_name="test_model",
+        field_name="test_field",
+        threshold="= 0",
+        missing_values=["N/A", "peter's"],
+    )
+
+    yaml_dict = yaml.safe_load(check.implementation)
+    missing_values = yaml_dict["checks for test_model"][0]["missing_count(test_field) = 0"]["missing values"]
+
+    assert missing_values == ["N/A", "peter''s"]