Dbdict.cpp:

  Bug #27710 Creating unique index fails during single user mode
  - enable indexes to be used always, if in single user, reject will happen before, and if it is kerlel doing stuff, it should always be allowed

ndb/src/kernel/blocks/dbdict/Dbdict.cpp

@@ -6883,6 +6883,7 @@ Dbdict::createIndex_toCreateTable(Signal* signal, OpCreateIndexPtr opPtr)
   w.add(DictTabInfo::NoOfKeyAttr, indexPtr.p->noOfPrimkey);
   w.add(DictTabInfo::NoOfNullable, indexPtr.p->noOfNullAttr);
   w.add(DictTabInfo::KeyLength, indexPtr.p->tupKeyLength);
+  w.add(DictTabInfo::SingleUserMode, (Uint32)1);
   // write index key attributes
   AttributeRecordPtr aRecPtr;
   c_attributeRecordPool.getPtr(aRecPtr, tablePtr.p->firstAttribute);