DDL bypass plan

go/vt/vtgate/planbuilder/ddl.go

@@ -51,6 +51,9 @@ func (fk *fkContraint) FkWalk(node sqlparser.SQLNode) (kontinue bool, err error)
 // This is why we return a compound primitive (DDL) which contains fully populated primitives (Send & OnlineDDL),
 // and which chooses which of the two to invoke at runtime.
 func buildGeneralDDLPlan(sql string, ddlStatement sqlparser.DDLStatement, reservedVars *sqlparser.ReservedVars, vschema ContextVSchema) (engine.Primitive, error) {
+	if vschema.Destination() != nil {
+		return buildByPassDDLPlan(sql, vschema)
+	}
 	normalDDLPlan, onlineDDLPlan, err := buildDDLPlans(sql, ddlStatement, reservedVars, vschema)
 	if err != nil {
 		return nil, err
@@ -76,6 +79,18 @@ func buildGeneralDDLPlan(sql string, ddlStatement sqlparser.DDLStatement, reserv
 	}, nil
 }
 
+func buildByPassDDLPlan(sql string, vschema ContextVSchema) (engine.Primitive, error) {
+	keyspace, err := vschema.DefaultKeyspace()
+	if err != nil {
+		return nil, err
+	}
+	return &engine.Send{
+		Keyspace:          keyspace,
+		TargetDestination: vschema.Destination(),
+		Query:             sql,
+	}, nil
+}
+
 func buildDDLPlans(sql string, ddlStatement sqlparser.DDLStatement, reservedVars *sqlparser.ReservedVars, vschema ContextVSchema) (*engine.Send, *engine.OnlineDDL, error) {
 	var destination key.Destination
 	var keyspace *vindexes.Keyspace

go/vt/vtgate/planbuilder/testdata/bypass_cases.txt

@@ -156,3 +156,20 @@ Gen4 plan same as above
   }
 }
 Gen4 plan same as above
+
+# create table
+"create /* test */ table t1(id bigint, primary key(id)) /* comments */"
+{
+  "QueryType": "DDL",
+  "Original": "create /* test */ table t1(id bigint, primary key(id)) /* comments */",
+  "Instructions": {
+    "OperatorType": "Send",
+    "Keyspace": {
+      "Name": "main",
+      "Sharded": false
+    },
+    "TargetDestination": "Shard(-80)",
+    "Query": "create /* test */ table t1(id bigint, primary key(id)) /* comments */"
+  }
+}
+Gen4 plan same as above