presto-main/src/main/java/io/prestosql/sql/gen/OrderingCompiler.java/OrderingCompiler/equals
class OrderingCompiler:        @Override
        public boolean equals(Object obj)
        {
            if (this == obj) {
                return true;
            }
            if (obj == null || getClass() != obj.getClass()) {
                return false;
            }
            PagesIndexComparatorCacheKey other = (PagesIndexComparatorCacheKey) obj;
            return Objects.equals(this.sortTypes, other.sortTypes) &&
                    Objects.equals(this.sortChannels, other.sortChannels) &&
                    Objects.equals(this.sortOrders, other.sortOrders);
        }