See the Help File for the "RECOVER" parameter of Validate Database.

>When running the Validate on a Database that has been crashing sometimes. I received a message that "Tag not found in structural CDX for Table "Enforce"
>I opened the database and enforce exclusively and added the index and rebuilt the indexes. then ran cleanup and then re-validated the database. After doing that I have that the index is missing from the DBC. How to I rebuild the DBC or fix it?
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>This is a large database with over 2000 object.
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>There are 4 Index errors, and 1 message that "table is not in a database"