Method addProjection

server/src/main/java/io/crate/planner/Merge.java:138–148

(List<Projection> projections, @Nullable Projection projection)

    }

    private static List<Projection> addProjection(List<Projection> projections, @Nullable Projection projection) {
        if (projection == null) {
            return projections;
        }
        if (projections.isEmpty()) {
            return Collections.singletonList(projection);
        } else {
            projections.add(projection);
            return projections;
        }
    }

    public static ExecutionPlan ensureOnHandler(ExecutionPlan subExecutionPlan, PlannerContext plannerContext) {
        return ensureOnHandler(subExecutionPlan, plannerContext, Collections.emptyList());