martinv13 · Oct 20, 2026 · Oct 20, 2026 · Oct 20, 2026
diff --git a/docs/configuring.md b/docs/configuring.md
@@ -106,7 +106,7 @@ functions (defaults to `hashlib.sha1`).
 deduplication of rows is opted out. This allows recording the original order of elements in the source XML, which is not
 always respected otherwise. It was implemented primarily for round-trip tests, but could serve other purposes. The 
 default value is `False` (disabled).
-* `transform` (`false` or `"auto"`): set to `false` to disable all automatic field transformations globally: no joining of multi-value columns, no elevation of child tables, no collapsing of choice groups. The default `"auto"` applies all of these where applicable. Per-field `transform` and per-table `choice_transform` still override the global setting.
+* `transform` (`false` or `"auto"`): set to `false` to disable automatic field transformations globally: no elevation of child tables, no collapsing of choice groups. Multi-value columns are still joined, as opting out of `join` is not supported. The default `"auto"` applies all of these where applicable. Per-field `transform` and per-table `choice_transform` still override the global setting.
 
 ## Fields configuration
 

diff --git a/src/xml2db/table/transformed_table.py b/src/xml2db/table/transformed_table.py
@@ -150,12 +150,13 @@ def _get_field_transform(
                     f"Transform value '{field_transform}' cannot be applied"
                     f" to field '{field_name}' of table '{self.name}'."
                 )
+        # "join" is how simple values are read at parsing stage, so global transform:false does not turn it off
+        if field_type == "col":
+            if self._can_transform_field("col", field_name, "join"):
+                return "join"
         # "auto" at field level always runs auto-detection, overriding global transform:false
-        if field_transform == "auto" or self.data_model.model_config.get("transform", True):
-            if field_type == "col":
-                if self._can_transform_field("col", field_name, "join"):
-                    return "join"
-            elif field_type == "rel1":
+        elif field_transform == "auto" or self.data_model.model_config.get("transform", True):
+            if field_type == "rel1":
                 if (
                     self.relations_1[field_name].occurs[0] == 1
                     or len(self.relations_1[field_name].other_table.columns) <= 4

diff --git a/tests/sample_models/models.py b/tests/sample_models/models.py
@@ -74,11 +74,16 @@ def wrapped():
             {
                 "config": {
                     "tables": {
-                        "shiporder": {"reuse": False},
+                        "shiporder": {
+                            "reuse": False,
+                            # shipto is optional with many columns: auto-detection would not elevate it
+                            "fields": {"shipto": {"transform": "elevate"}},
+                        },
                         "item": {
                             "fields": {
                                 "product": {"transform": False},
                                 "comment": {"transform": "skip"},
+                                "quantity": {"type": "BigInteger"},
                             }
                         },
                     },
@@ -90,6 +95,24 @@ def wrapped():
                     ],
                 }
             },
+            {
+                "config": {
+                    "transform": False,
+                    "tables": {
+                        "item": {"fields": {"comment": {"transform": "skip"}}},
+                        # without elevation, an empty extra element would add a row
+                        "orderperson": {"fields": {"extra": {"transform": "skip"}}},
+                        # overrides the global transform: false
+                        "companyId": {"choice_transform": True},
+                    },
+                    "metadata_columns": [
+                        {
+                            "name": "input_file_path",
+                            "type": sqlalchemy.String(256),
+                        }
+                    ],
+                }
+            },
         ],
     },
     {

diff --git a/tests/sample_models/orders/orders_ddl_mssql_version2.sql b/tests/sample_models/orders/orders_ddl_mssql_version2.sql
@@ -10,6 +10,16 @@ CREATE TABLE orders (
 )
 
 
+CREATE TABLE detail_1 (
+	pk_detail_1 INTEGER NOT NULL IDENTITY, 
+	reference VARCHAR(1000) NULL, 
+	carrier VARCHAR(1000) NULL, 
+	xml2db_record_hash BINARY(20) NULL, 
+	CONSTRAINT cx_pk_detail_1 PRIMARY KEY CLUSTERED (pk_detail_1), 
+	CONSTRAINT detail_1_xml2db_record_hash UNIQUE (xml2db_record_hash)
+)
+
+
 CREATE TABLE orderperson (
 	pk_orderperson INTEGER NOT NULL IDENTITY, 
 	name_attr VARCHAR(1000) NULL, 
@@ -31,16 +41,6 @@ CREATE TABLE orderperson (
 )
 
 
-CREATE TABLE detail_1 (
-	pk_detail_1 INTEGER NOT NULL IDENTITY, 
-	reference VARCHAR(1000) NULL, 
-	carrier VARCHAR(1000) NULL, 
-	xml2db_record_hash BINARY(20) NULL, 
-	CONSTRAINT cx_pk_detail_1 PRIMARY KEY CLUSTERED (pk_detail_1), 
-	CONSTRAINT detail_1_xml2db_record_hash UNIQUE (xml2db_record_hash)
-)
-
-
 CREATE TABLE detail (
 	pk_detail INTEGER NOT NULL IDENTITY, 
 	weight DOUBLE PRECISION NULL, 
@@ -101,7 +101,7 @@ CREATE TABLE item (
 	pk_item INTEGER NOT NULL IDENTITY, 
 	fk_product INTEGER NULL, 
 	note VARCHAR(1000) NULL, 
-	quantity INTEGER NULL, 
+	quantity BIGINT NULL, 
 	price DOUBLE PRECISION NULL, 
 	currency CHAR(3) NULL, 
 	delivery_from_fk_orderperson INTEGER NULL, 
@@ -144,12 +144,23 @@ CREATE TABLE shiporder (
 	[orderperson_companyId_value] VARCHAR(1000) NULL, 
 	orderperson_coordinates VARCHAR(1000) NULL, 
 	orderperson_a_very_long_field_type_that_makes_col_name_exceeds_max_identifier_length VARCHAR(1000) NULL, 
-	shipto_fk_orderperson INTEGER NULL, 
+	shipto_name_attr VARCHAR(1000) NULL, 
+	shipto_name VARCHAR(1000) NULL, 
+	shipto_address VARCHAR(1000) NULL, 
+	shipto_city VARCHAR(1000) NULL, 
+	[shipto_zip_codingSystem] VARCHAR(1000) NULL, 
+	shipto_zip_state VARCHAR(1000) NULL, 
+	shipto_zip_value VARCHAR(1000) NULL, 
+	shipto_country VARCHAR(1000) NULL, 
+	[shipto_phoneNumber] VARCHAR(8000) NULL, 
+	[shipto_companyId_type] CHAR(3) NULL, 
+	[shipto_companyId_value] VARCHAR(1000) NULL, 
+	shipto_coordinates VARCHAR(1000) NULL, 
+	shipto_a_very_long_field_type_that_makes_col_name_exceeds_max_identifier_length VARCHAR(1000) NULL, 
 	[carrierId_vat] VARCHAR(1000) NULL, 
 	[carrierId_registry] VARCHAR(1000) NULL, 
 	CONSTRAINT cx_pk_shiporder PRIMARY KEY CLUSTERED (pk_shiporder), 
-	FOREIGN KEY(fk_parent_orders) REFERENCES orders (pk_orders), 
-	FOREIGN KEY(shipto_fk_orderperson) REFERENCES orderperson (pk_orderperson)
+	FOREIGN KEY(fk_parent_orders) REFERENCES orders (pk_orders)
 )
 
 

diff --git a/tests/sample_models/orders/orders_ddl_mssql_version3.sql b/tests/sample_models/orders/orders_ddl_mssql_version3.sql
@@ -0,0 +1,250 @@
+
+CREATE TABLE [carrierId] (
+	[pk_carrierId] INTEGER NOT NULL IDENTITY, 
+	vat VARCHAR(1000) NULL, 
+	registry VARCHAR(1000) NULL, 
+	xml2db_record_hash BINARY(20) NULL, 
+	CONSTRAINT [cx_pk_carrierId] PRIMARY KEY CLUSTERED ([pk_carrierId]), 
+	CONSTRAINT [carrierId_xml2db_record_hash] UNIQUE (xml2db_record_hash)
+)
+
+
+CREATE TABLE detail_1 (
+	pk_detail_1 INTEGER NOT NULL IDENTITY, 
+	reference VARCHAR(1000) NULL, 
+	carrier VARCHAR(1000) NULL, 
+	xml2db_record_hash BINARY(20) NULL, 
+	CONSTRAINT cx_pk_detail_1 PRIMARY KEY CLUSTERED (pk_detail_1), 
+	CONSTRAINT detail_1_xml2db_record_hash UNIQUE (xml2db_record_hash)
+)
+
+
+CREATE TABLE zip (
+	pk_zip INTEGER NOT NULL IDENTITY, 
+	[codingSystem] VARCHAR(1000) NULL, 
+	state VARCHAR(1000) NULL, 
+	value VARCHAR(1000) NULL, 
+	xml2db_record_hash BINARY(20) NULL, 
+	CONSTRAINT cx_pk_zip PRIMARY KEY CLUSTERED (pk_zip), 
+	CONSTRAINT zip_xml2db_record_hash UNIQUE (xml2db_record_hash)
+)
+
+
+CREATE TABLE [companyId] (
+	[pk_companyId] INTEGER NOT NULL IDENTITY, 
+	type CHAR(3) NULL, 
+	value VARCHAR(1000) NULL, 
+	xml2db_record_hash BINARY(20) NULL, 
+	CONSTRAINT [cx_pk_companyId] PRIMARY KEY CLUSTERED ([pk_companyId]), 
+	CONSTRAINT [companyId_xml2db_record_hash] UNIQUE (xml2db_record_hash)
+)
+
+
+CREATE TABLE catalog_ref (
+	pk_catalog_ref INTEGER NOT NULL IDENTITY, 
+	id VARCHAR(1000) NULL, 
+	urn VARCHAR(1000) NULL, 
+	xml2db_record_hash BINARY(20) NULL, 
+	CONSTRAINT cx_pk_catalog_ref PRIMARY KEY CLUSTERED (pk_catalog_ref), 
+	CONSTRAINT catalog_ref_xml2db_record_hash UNIQUE (xml2db_record_hash)
+)
+
+
+CREATE TABLE detail (
+	pk_detail INTEGER NOT NULL IDENTITY, 
+	weight DOUBLE PRECISION NULL, 
+	unit VARCHAR(1000) NULL, 
+	xml2db_record_hash BINARY(20) NULL, 
+	CONSTRAINT cx_pk_detail PRIMARY KEY CLUSTERED (pk_detail), 
+	CONSTRAINT detail_xml2db_record_hash UNIQUE (xml2db_record_hash)
+)
+
+
+CREATE TABLE intfeature_with_peculiarly_long_suffix_which_overflow_max_length (
+	pk_intfeature_with_peculiarly_long_suffix_which_overflow_max_length INTEGER NOT NULL IDENTITY, 
+	id VARCHAR(1000) NULL, 
+	value INTEGER NULL, 
+	xml2db_record_hash BINARY(20) NULL, 
+	CONSTRAINT cx_pk_intfeature_with_peculiarly_long_suffix_which_overflow_max_length PRIMARY KEY CLUSTERED (pk_intfeature_with_peculiarly_long_suffix_which_overflow_max_length), 
+	CONSTRAINT intfeature_with_peculia_0c087_xml2db_record_hash UNIQUE (xml2db_record_hash)
+)
+
+
+CREATE TABLE stringfeature (
+	pk_stringfeature INTEGER NOT NULL IDENTITY, 
+	id VARCHAR(1000) NULL, 
+	value VARCHAR(1000) NULL, 
+	xml2db_record_hash BINARY(20) NULL, 
+	CONSTRAINT cx_pk_stringfeature PRIMARY KEY CLUSTERED (pk_stringfeature), 
+	CONSTRAINT stringfeature_xml2db_record_hash UNIQUE (xml2db_record_hash)
+)
+
+
+CREATE TABLE orderperson (
+	pk_orderperson INTEGER NOT NULL IDENTITY, 
+	name_attr VARCHAR(1000) NULL, 
+	name VARCHAR(1000) NULL, 
+	address VARCHAR(1000) NULL, 
+	city VARCHAR(1000) NULL, 
+	fk_zip INTEGER NULL, 
+	country VARCHAR(1000) NULL, 
+	[phoneNumber] VARCHAR(8000) NULL, 
+	[fk_companyId] INTEGER NULL, 
+	coordinates VARCHAR(1000) NULL, 
+	a_very_long_field_type_that_makes_col_name_exceeds_max_identifier_length VARCHAR(1000) NULL, 
+	xml2db_record_hash BINARY(20) NULL, 
+	CONSTRAINT cx_pk_orderperson PRIMARY KEY CLUSTERED (pk_orderperson), 
+	CONSTRAINT orderperson_xml2db_record_hash UNIQUE (xml2db_record_hash), 
+	FOREIGN KEY(fk_zip) REFERENCES zip (pk_zip), 
+	FOREIGN KEY([fk_companyId]) REFERENCES [companyId] ([pk_companyId])
+)
+
+
+CREATE TABLE features (
+	pk_features INTEGER NOT NULL IDENTITY, 
+	xml2db_record_hash BINARY(20) NULL, 
+	CONSTRAINT cx_pk_features PRIMARY KEY CLUSTERED (pk_features), 
+	CONSTRAINT features_xml2db_record_hash UNIQUE (xml2db_record_hash)
+)
+
+
+CREATE TABLE features_intfeature_with_peculiarly_long_suffix_which_overflow_max_length (
+	fk_features INTEGER NOT NULL, 
+	fk_intfeature_with_peculiarly_long_suffix_which_overflow_max_length INTEGER NOT NULL, 
+	FOREIGN KEY(fk_features) REFERENCES features (pk_features), 
+	FOREIGN KEY(fk_intfeature_with_peculiarly_long_suffix_which_overflow_max_length) REFERENCES intfeature_with_peculiarly_long_suffix_which_overflow_max_length (pk_intfeature_with_peculiarly_long_suffix_which_overflow_max_length)
+)
+
+
+CREATE TABLE features_stringfeature (
+	fk_features INTEGER NOT NULL, 
+	fk_stringfeature INTEGER NOT NULL, 
+	FOREIGN KEY(fk_features) REFERENCES features (pk_features), 
+	FOREIGN KEY(fk_stringfeature) REFERENCES stringfeature (pk_stringfeature)
+)
+
+
+CREATE TABLE delivery (
+	pk_delivery INTEGER NOT NULL IDENTITY, 
+	from_fk_orderperson INTEGER NULL, 
+	to_fk_orderperson INTEGER NULL, 
+	xml2db_record_hash BINARY(20) NULL, 
+	CONSTRAINT cx_pk_delivery PRIMARY KEY CLUSTERED (pk_delivery), 
+	CONSTRAINT delivery_xml2db_record_hash UNIQUE (xml2db_record_hash), 
+	FOREIGN KEY(from_fk_orderperson) REFERENCES orderperson (pk_orderperson), 
+	FOREIGN KEY(to_fk_orderperson) REFERENCES orderperson (pk_orderperson)
+)
+
+
+CREATE TABLE product (
+	pk_product INTEGER NOT NULL IDENTITY, 
+	name VARCHAR(1000) NULL, 
+	version VARCHAR(1000) NULL, 
+	fk_features INTEGER NULL, 
+	xml2db_record_hash BINARY(20) NULL, 
+	CONSTRAINT cx_pk_product PRIMARY KEY CLUSTERED (pk_product), 
+	CONSTRAINT product_xml2db_record_hash UNIQUE (xml2db_record_hash), 
+	FOREIGN KEY(fk_features) REFERENCES features (pk_features)
+)
+
+
+CREATE TABLE item (
+	pk_item INTEGER NOT NULL IDENTITY, 
+	fk_product INTEGER NULL, 
+	note VARCHAR(1000) NULL, 
+	quantity INTEGER NULL, 
+	price DOUBLE PRECISION NULL, 
+	currency CHAR(3) NULL, 
+	fk_delivery INTEGER NULL, 
+	fk_catalog_ref INTEGER NULL, 
+	xml2db_record_hash BINARY(20) NULL, 
+	CONSTRAINT cx_pk_item PRIMARY KEY CLUSTERED (pk_item), 
+	CONSTRAINT item_xml2db_record_hash UNIQUE (xml2db_record_hash), 
+	FOREIGN KEY(fk_product) REFERENCES product (pk_product), 
+	FOREIGN KEY(fk_delivery) REFERENCES delivery (pk_delivery), 
+	FOREIGN KEY(fk_catalog_ref) REFERENCES catalog_ref (pk_catalog_ref)
+)
+
+
+CREATE TABLE item_detail (
+	fk_item INTEGER NOT NULL, 
+	fk_detail INTEGER NOT NULL, 
+	FOREIGN KEY(fk_item) REFERENCES item (pk_item), 
+	FOREIGN KEY(fk_detail) REFERENCES detail (pk_detail)
+)
+
+
+CREATE TABLE shiporder (
+	pk_shiporder INTEGER NOT NULL IDENTITY, 
+	orderid VARCHAR(1000) NULL, 
+	processed_at DATETIMEOFFSET NULL, 
+	fk_orderperson INTEGER NULL, 
+	shipto_fk_orderperson INTEGER NULL, 
+	[fk_carrierId] INTEGER NULL, 
+	xml2db_record_hash BINARY(20) NULL, 
+	CONSTRAINT cx_pk_shiporder PRIMARY KEY CLUSTERED (pk_shiporder), 
+	CONSTRAINT shiporder_xml2db_record_hash UNIQUE (xml2db_record_hash), 
+	FOREIGN KEY(fk_orderperson) REFERENCES orderperson (pk_orderperson), 
+	FOREIGN KEY(shipto_fk_orderperson) REFERENCES orderperson (pk_orderperson), 
+	FOREIGN KEY([fk_carrierId]) REFERENCES [carrierId] ([pk_carrierId])
+)
+
+
+CREATE TABLE shiporder_item (
+	fk_shiporder INTEGER NOT NULL, 
+	fk_item INTEGER NOT NULL, 
+	FOREIGN KEY(fk_shiporder) REFERENCES shiporder (pk_shiporder), 
+	FOREIGN KEY(fk_item) REFERENCES item (pk_item)
+)
+
+
+CREATE TABLE shiporder_detail_detail_1 (
+	fk_shiporder INTEGER NOT NULL, 
+	fk_detail_1 INTEGER NOT NULL, 
+	FOREIGN KEY(fk_shiporder) REFERENCES shiporder (pk_shiporder), 
+	FOREIGN KEY(fk_detail_1) REFERENCES detail_1 (pk_detail_1)
+)
+
+
+CREATE TABLE orders (
+	pk_orders INTEGER NOT NULL IDENTITY, 
+	batch_id VARCHAR(1000) NULL, 
+	version INTEGER NULL, 
+	input_file_path VARCHAR(256) NULL, 
+	xml2db_record_hash BINARY(20) NULL, 
+	CONSTRAINT cx_pk_orders PRIMARY KEY CLUSTERED (pk_orders), 
+	CONSTRAINT orders_xml2db_record_hash UNIQUE (xml2db_record_hash)
+)
+
+
+CREATE TABLE orders_shiporder (
+	fk_orders INTEGER NOT NULL, 
+	fk_shiporder INTEGER NOT NULL, 
+	FOREIGN KEY(fk_orders) REFERENCES orders (pk_orders), 
+	FOREIGN KEY(fk_shiporder) REFERENCES shiporder (pk_shiporder)
+)
+
+CREATE INDEX ix_features_intfeature_with_peculiarly_long_suffix_which_overflow_max_length_fk_intfeature_with_peculiarly_long_suffix_w_ef47 ON features_intfeature_with_peculiarly_long_suffix_which_overflow_max_length (fk_intfeature_with_peculiarly_long_suffix_which_overflow_max_length)
+
+CREATE CLUSTERED INDEX ix_fk_features_intfeature_with_peculiarly_long_suffix_which_overflow_max_length ON features_intfeature_with_peculiarly_long_suffix_which_overflow_max_length (fk_features, fk_intfeature_with_peculiarly_long_suffix_which_overflow_max_length)
+
+CREATE INDEX ix_features_stringfeature_fk_stringfeature ON features_stringfeature (fk_stringfeature)
+
+CREATE CLUSTERED INDEX ix_fk_features_stringfeature ON features_stringfeature (fk_features, fk_stringfeature)
+
+CREATE CLUSTERED INDEX ix_fk_item_detail ON item_detail (fk_item, fk_detail)
+
+CREATE INDEX ix_item_detail_fk_detail ON item_detail (fk_detail)
+
+CREATE CLUSTERED INDEX ix_fk_shiporder_item ON shiporder_item (fk_shiporder, fk_item)
+
+CREATE INDEX ix_shiporder_item_fk_item ON shiporder_item (fk_item)
+
+CREATE CLUSTERED INDEX ix_fk_shiporder_detail_detail_1 ON shiporder_detail_detail_1 (fk_shiporder, fk_detail_1)
+
+CREATE INDEX ix_shiporder_detail_detail_1_fk_detail_1 ON shiporder_detail_detail_1 (fk_detail_1)
+
+CREATE CLUSTERED INDEX ix_fk_orders_shiporder ON orders_shiporder (fk_orders, fk_shiporder)
+
+CREATE INDEX ix_orders_shiporder_fk_shiporder ON orders_shiporder (fk_shiporder)
+