A SNOMED CT International Release includes three distinct release types. Table 3.2-1 describes the release types and the differences between them.
A full release is
a release type in which the release files contain every version of every component and reference set member ever released.
A snapshot release is
a release type in which the release files contain only the most recent version of every component and reference set member released, as at the release date.
A delta release is
a release type in which the release files contain only rows that represent component versions and reference set member versions created since the previous release date.
Please note :
There are practical use cases for each Release Type.
When considering which release type to use, it is worth noting that delta and snapshot views can be readily generated from the full release type. For this reason organizations that maintain SNOMED CT extensions are required to provide the full release type, while distribution of the other release types are optional.