Segment vs Partition?

I am using ColumnStore. What is the difference between row segment and data partitions. Do row segments come under partitions?

MemSQL databases are divided into multiple partitions based on a hash function. Each leaf node stores one or more partitions of a database. The portion of a columnstore table within one partition is further divided into segments. Be default, segments are million-row chunks of a table.


A partition is a division of a storage device described in the partition map, which may contain a volume. A volume comprises the bytes that contain a filesystem.

An unpartitioned device, such as a floppy, contains a volume but does not contain a partition.

I’ve never heard of “segment.” Google gives : , which defines that as any logically contiguous range of sectors.