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Explanation on the projections <table_name>_pk

Hello

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

Isabelle

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