code: private String constructSinglePathSql(
              SqlgGraph sqlgGraph,
              boolean partOfDuplicateQuery,
              LinkedList<SchemaTableTree> distinctQueryStack,
              SchemaTableTree lastOfPrevious,
              SchemaTableTree firstOfNextStack,
              Set<SchemaTableTree> leftJoinOn,
              boolean dropStep) {
  
          return constructSelectSinglePathSql(
                  sqlgGraph,
                  partOfDuplicateQuery,
                  distinctQueryStack,
                  lastOfPrevious,
                  firstOfNextStack,
                  leftJoinOn,
                  dropStep);
      }
docs: Constructs a sql select statement from the SchemaTableTree call stack.
  The SchemaTableTree is not used as a tree. It is used only as as SchemaTable with a direction.
  first and last is needed to facilitate generating the from statement.
  If both first and last is true then the gremlin does not contain duplicate labels in its path and
  can be executed in one sql statement.
  If first and last is not equal then the sql will join across many select statements.
  The previous select needs to join onto the subsequent select. For this the from needs to select the appropriate
  field for the join.