multiFK2

common/proto/table_definition.proto

@@ -53,16 +53,18 @@ message PostTableDefinitionRequest {
   // Table name to create inside the target profile.
   // Must be lowercase, alphanumeric with underscores,
   // start with a letter, and be <= 63 chars.
-  // Forbidden names: "id", "deleted", "created_at", "row_revision", or ending in "_id".
+  // Forbidden names: "id", "deleted", "created_at", "row_revision" -- the
+  // system columns, which share one namespace with table names wherever the
+  // two are named side by side. The "_id" suffix is allowed.
   string table_name = 1;
 
-  // List of user-defined columns (adds to system/id/fk columns).
+  // The table's columns, including its links. System columns are added on top.
   repeated ColumnDefinition columns = 3;
 
-  // List of column names to be indexed (must match existing user-defined columns).
+  // Column names to index, matching names declared above. System columns
-  // Indexes can target only user-defined columns; system columns ("id", "deleted",
+  // ("id", "deleted", "created_at", "row_revision") already have indexes, and
-  // "created_at", "row_revision") and automatically generated foreign key ("*_id") columns already
+  // a LINK column is indexed when it is created. Requests naming either are
-  // have indexes. Requests trying to index those columns are rejected.
+  // rejected.
   repeated string indexes = 4;
 
   // Name of profile (Postgres schema) where the table will be created.
@@ -142,9 +144,13 @@ enum MoneyRounding {
 
 // Describes one user-defined column for a table.
 message ColumnDefinition {
-  // Column name that follows the same validation rules as table_name.
+  // Must be lowercase, start with a letter, and use only lowercase letters,
-  // Must be lowercase, start with a letter, no uppercase characters,
+  // digits and underscores.
-  // and cannot be "id", "deleted", "created_at", "row_revision", or end with "_id".
+  //
+  // Cannot be "id", "deleted", "created_at" or "row_revision": those are
+  // system columns, and a data request names system and user columns in one
+  // namespace. Any other name is free, including one ending in "_id" -- no
+  // column name is derived from a table name, so nothing collides.
   string name = 1;
 
   // Logical column type. Supported values (case-insensitive):

common/proto/table_script.proto

@@ -181,6 +181,16 @@ message ScriptDependency {
   string operation = 4;
   // Relationship table used to match the owner row to the related collection.
   string via_table = 5;
+  // Column of the current row holding the referenced row's id: the link this
+  // dependency travels, resolved when the script was saved. Empty when no link
+  // is travelled -- a self-reference, or an aggregate, which follows a path
+  // instead. A table may link to one target several times, so this is the only
+  // thing that says which link was meant; never derive it from target_table.
+  string link_column = 6;
+  // The first argument exactly as the script wrote it: a link alias, or the
+  // target table's name where one link makes that unambiguous. The Steel
+  // runtime looks its inputs up by this text.
+  string name_in_script = 7;
 }
 
 // Identifies the active form row whose external Steel inputs must be hydrated.

common/proto/table_structure.proto

@@ -46,7 +46,7 @@ message GetTableStructureResponse {
 message TableStructureResponse {
   // Columns of the physical table, including system columns (id, deleted,
   // created_at, row_revision), user-defined columns, and any foreign-key columns such as
-  // "<linked_table>_id", plus the dedicated "account_id" column on
+  // named by whoever declared each link, plus the dedicated "account_id" on
   // ACCOUNTING-enabled tables. May be empty if the physical table is missing.
   repeated TableColumn columns = 1;
 }

common/proto/tables_data.proto

@@ -62,7 +62,7 @@ service TablesData {
   // - Validates profile and table definition
   // - Returns all columns as strings (COALESCE(col::TEXT, '') AS col)
   //   including: id, deleted, row_revision, all user-defined columns, and FK columns
-  //   named "<linked_table>_id" for each table link, plus "account_id" on
+  //   named by whoever declared each link, plus "account_id" on
   //   ACCOUNTING-enabled tables
   // - Fails with NOT_FOUND if record does not exist or is soft-deleted
   // - If the physical table is missing but the definition exists, returns INTERNAL
@@ -101,7 +101,7 @@ message PostTableDataRequest {
   // - User-defined columns from the table definition
   // - System/FK columns:
   //    • "deleted" (BOOLEAN), optional; default FALSE if not provided
-  //    • "<linked_table>_id" (BIGINT) for each table link
+  //    • one BIGINT per link, named by whoever declared it
   //    • "account_id" (BIGINT) on ACCOUNTING-enabled tables
   //
   // Type expectations by SQL type:
@@ -250,7 +250,7 @@ message GetTableDataResponse {
   // Map of column_name → stringified value for:
   // - id, deleted
   // - all user-defined columns from the table definition
-  // - FK columns named "<linked_table>_id" for each table link
+  // - one column per link, named by whoever declared it
   // - account_id for ACCOUNTING-enabled tables
   //
   // All values are returned as TEXT via col::TEXT and COALESCEed to empty string

common/src/proto/komp_ac.table_definition.rs

@@ -6,16 +6,18 @@ pub struct PostTableDefinitionRequest {
     /// Table name to create inside the target profile.
     /// Must be lowercase, alphanumeric with underscores,
     /// start with a letter, and be \<= 63 chars.
-    /// Forbidden names: "id", "deleted", "created_at", "row_revision", or ending in "\_id".
+    /// Forbidden names: "id", "deleted", "created_at", "row_revision" -- the
+    /// system columns, which share one namespace with table names wherever the
+    /// two are named side by side. The "\_id" suffix is allowed.
     #[prost(string, tag = "1")]
     pub table_name: ::prost::alloc::string::String,
-    /// List of user-defined columns (adds to system/id/fk columns).
+    /// The table's columns, including its links. System columns are added on top.
     #[prost(message, repeated, tag = "3")]
     pub columns: ::prost::alloc::vec::Vec<ColumnDefinition>,
-    /// List of column names to be indexed (must match existing user-defined columns).
+    /// Column names to index, matching names declared above. System columns
-    /// Indexes can target only user-defined columns; system columns ("id", "deleted",
+    /// ("id", "deleted", "created_at", "row_revision") already have indexes, and
-    /// "created_at", "row_revision") and automatically generated foreign key ("\*\_id") columns already
+    /// a LINK column is indexed when it is created. Requests naming either are
-    /// have indexes. Requests trying to index those columns are rejected.
+    /// rejected.
     #[prost(string, repeated, tag = "4")]
     pub indexes: ::prost::alloc::vec::Vec<::prost::alloc::string::String>,
     /// Name of profile (Postgres schema) where the table will be created.
@@ -106,9 +108,13 @@ pub struct AddTableColumnsRequest {
 #[derive(serde::Serialize, serde::Deserialize)]
 #[derive(Clone, PartialEq, Eq, Hash, ::prost::Message)]
 pub struct ColumnDefinition {
-    /// Column name that follows the same validation rules as table_name.
+    /// Must be lowercase, start with a letter, and use only lowercase letters,
-    /// Must be lowercase, start with a letter, no uppercase characters,
+    /// digits and underscores.
-    /// and cannot be "id", "deleted", "created_at", "row_revision", or end with "\_id".
+    ///
+    /// Cannot be "id", "deleted", "created_at" or "row_revision": those are
+    /// system columns, and a data request names system and user columns in one
+    /// namespace. Any other name is free, including one ending in "\_id" -- no
+    /// column name is derived from a table name, so nothing collides.
     #[prost(string, tag = "1")]
     pub name: ::prost::alloc::string::String,
     /// Logical column type. Supported values (case-insensitive):

common/src/proto/komp_ac.table_script.rs

@@ -127,6 +127,18 @@ pub struct ScriptDependency {
     /// Relationship table used to match the owner row to the related collection.
     #[prost(string, tag = "5")]
     pub via_table: ::prost::alloc::string::String,
+    /// Column of the current row holding the referenced row's id: the link this
+    /// dependency travels, resolved when the script was saved. Empty when no link
+    /// is travelled -- a self-reference, or an aggregate, which follows a path
+    /// instead. A table may link to one target several times, so this is the only
+    /// thing that says which link was meant; never derive it from target_table.
+    #[prost(string, tag = "6")]
+    pub link_column: ::prost::alloc::string::String,
+    /// The first argument exactly as the script wrote it: a link alias, or the
+    /// target table's name where one link makes that unambiguous. The Steel
+    /// runtime looks its inputs up by this text.
+    #[prost(string, tag = "7")]
+    pub name_in_script: ::prost::alloc::string::String,
 }
 /// Identifies the active form row whose external Steel inputs must be hydrated.
 #[derive(Clone, PartialEq, ::prost::Message)]

common/src/proto/komp_ac.table_structure.rs

@@ -26,7 +26,7 @@ pub struct GetTableStructureResponse {
 pub struct TableStructureResponse {
     /// Columns of the physical table, including system columns (id, deleted,
     /// created_at, row_revision), user-defined columns, and any foreign-key columns such as
-    /// "\<linked_table>\_id", plus the dedicated "account_id" column on
+    /// named by whoever declared each link, plus the dedicated "account_id" on
     /// ACCOUNTING-enabled tables. May be empty if the physical table is missing.
     #[prost(message, repeated, tag = "1")]
     pub columns: ::prost::alloc::vec::Vec<TableColumn>,

common/src/proto/komp_ac.tables_data.rs

@@ -17,7 +17,7 @@ pub struct PostTableDataRequest {
     /// * User-defined columns from the table definition
     /// * System/FK columns:
     ///   • "deleted" (BOOLEAN), optional; default FALSE if not provided
-    ///   • "\<linked_table>\_id" (BIGINT) for each table link
+    ///   • one BIGINT per link, named by whoever declared it
     ///   • "account_id" (BIGINT) on ACCOUNTING-enabled tables
     ///
     /// Type expectations by SQL type:
@@ -190,7 +190,7 @@ pub struct GetTableDataResponse {
     ///
     /// * id, deleted
     /// * all user-defined columns from the table definition
-    /// * FK columns named "\<linked_table>\_id" for each table link
+    /// * one column per link, named by whoever declared it
     /// * account_id for ACCOUNTING-enabled tables
     ///
     /// All values are returned as TEXT via col::TEXT and COALESCEed to empty string
@@ -482,7 +482,7 @@ pub mod tables_data_client {
         /// * Validates profile and table definition
         /// * Returns all columns as strings (COALESCE(col::TEXT, '') AS col)
         ///  including: id, deleted, row_revision, all user-defined columns, and FK columns
-        ///  named "\<linked_table>\_id" for each table link, plus "account_id" on
+        ///  named by whoever declared each link, plus "account_id" on
         ///  ACCOUNTING-enabled tables
         /// * Fails with NOT_FOUND if record does not exist or is soft-deleted
         /// * If the physical table is missing but the definition exists, returns INTERNAL
@@ -675,7 +675,7 @@ pub mod tables_data_server {
         /// * Validates profile and table definition
         /// * Returns all columns as strings (COALESCE(col::TEXT, '') AS col)
         ///  including: id, deleted, row_revision, all user-defined columns, and FK columns
-        ///  named "\<linked_table>\_id" for each table link, plus "account_id" on
+        ///  named by whoever declared each link, plus "account_id" on
         ///  ACCOUNTING-enabled tables
         /// * Fails with NOT_FOUND if record does not exist or is soft-deleted
         /// * If the physical table is missing but the definition exists, returns INTERNAL

web/src/schema/mod.rs

@@ -670,12 +670,11 @@ pub(crate) fn validate_identifier(
             "{label} may only use lowercase letters, digits and underscores."
         ));
     }
+    // Only the system columns are reserved. The `_id` suffix is free: no
+    // column name is derived from a table name any more, so it collides with
+    // nothing.
     if reject_table_reserved
-        && (value == "id"
+        && matches!(value, "id" | "deleted" | "created_at" | "row_revision")
-            || value == "deleted"
-            || value == "created_at"
-            || value == "row_revision"
-            || value.ends_with("_id"))
     {
         return Some(format!("{label} uses a reserved name."));
     }
@@ -1127,8 +1126,6 @@ pub(crate) mod tests {
 
         draft.name_input = "Total".to_string();
         assert!(draft.add_from_inputs().is_err());
-        draft.name_input = "customer_id".to_string();
-        assert!(draft.add_from_inputs().is_err());
         draft.name_input = "created_at".to_string();
         assert!(draft.add_from_inputs().is_err());
 
@@ -1334,3 +1331,27 @@ pub(crate) mod tests {
         assert_eq!(draft.selected_index_names(), vec!["number"]);
     }
 }
+
+#[cfg(test)]
+mod link_alias_tests {
+    use super::validate_identifier;
+
+    /// The `_id` suffix is an ordinary part of a column's name: nothing is
+    /// derived from a table name any more.
+    #[test]
+    fn a_column_name_may_end_in_id() {
+        assert_eq!(validate_identifier("external_id", "Column name", true), None);
+    }
+
+    /// The system columns stay reserved, since they share one namespace with
+    /// user columns in a data request.
+    #[test]
+    fn the_system_columns_stay_reserved() {
+        for name in ["id", "deleted", "created_at", "row_revision"] {
+            assert!(
+                validate_identifier(name, "Column name", true).is_some(),
+                "`{name}` must stay reserved"
+            );
+        }
+    }
+}