===== Key =====
[[dido:public:ra:xapend:xapend.a_glossary:start| Return to Glossary ]]


A **Key** is one or more fields within the data type. A key uniquely identifies one [[dido:public:ra:xapend:xapend.a_glossary:i:instance|instance]] of a [[dido:public:ra:xapend:xapend.a_glossary:t:topic|Topic]] from another instance of the same Topic. 

Source: [[https://community.rti.com/static/documentation/connext-dds/5.2.3/doc/manuals/connext_dds/html_files/RTI_ConnextDDS_CoreLibraries_UsersManual/Content/UsersManual/DDS_Samples__Instances__and_Keys.htm | Key ]]