Explanation on the projections <table_name>_pk
These projections are automatically created to enforce primary keys, they only contain the primary key column(s) and are segmented, but some points are not clear to me and I can't find documentation around. Any support is welcome to better understand them:
- what are they used for (pre -join? PK checks ? other ?)
what triggers their creation ?
- they are not always created at table load time, even if the primary key is enabled
- sometimes they are proposed when we run an Comprehensive or Incremental DBD
- in the same Design, we can have these projections proposed for some tables having a pk and not for others also having a pk....
- sometimes, even if one exists already, the DBD proposes exactly the same projection (same encoding) , either with name _pk_v1 or with _ without the pk suffix
is it a problem if tables with PK don't have a _pk projection ? what is the impact ?
Thanks a lot to those who know , of for any link to documentation about that