gql conformance update

Author: JPryce-Aklundh

modules/ROOT/pages/appendix/gql-conformance/supported-optional.adoc

@@ -98,6 +98,18 @@ These codes order the features in the table below.
 | xref:syntax/naming.adoc#identifier-length-limit[Naming rules and recommendations -> Identifier length limit]
 |
 
+| GD01
+| Updatable graphs
+| xref:clauses/clause-composition.adoc#writing-clauses[Cypher clauses -> Writing clauses]
+| * Feature GD01 implies compliance with GQL feature GT01, "Explicit transaction commands", which states that conforming languages shall contain the following transaction control commands: `START TRANSACTION`, `ROLLBACK`, and `COMMIT`.
+These are not present in Cypher.
+However, Neo4j offers transaction management through the link:{neo4j-docs-base-uri}/create-applications[driver] transaction API.
+Cypher Shell also offers specific link:{neo4j-docs-base-uri}/operations-manual/current/tools/cypher-shell/#cypher-shell-commands[commands] to manage transactions.
+* Feature GD01 implies conformance to GQL's `<set-statement>` (subclause 13.3).
+GQL’s `SET` has no order dependencies because all right-hand side operations are completed before any assignments occur.
+However, In Cypher’s `SET`, the order of rows can affect the outcome because changes made during execution may depend on the sequence of assignments.
+The only way to guarantee row order in Neo4j is to use xref:clauses/order-by.adoc[`ORDER BY`]. 
+
 | GF01
 | Enhanced numeric functions
 | xref:functions/mathematical-numeric.adoc#functions-abs[`abs()`], xref:functions/mathematical-numeric.adoc#functions-floor[`floor()`], xref:functions/mathematical-logarithmic.adoc#functions-sqrt[`sqrt()`].