ALTER INDEX [schema.]index_name REBUILD 
  [PARAMETERS('UPDATE VECTOR INDEX')]
  [PARALLEL n];

[schema.]index_name

Specifies name of the hybrid vector index that you want to modify.

PARAMETERS(UPDATE VECTOR INDEX)

Recreates only the vector index part of a hybrid vector index with the original preference settings.

PARALLEL

Specifies parallel indexing, as described for the CREATE HYBRID VECTOR INDEX statement.

For detailed information on the PARALLEL clause, see CREATE HYBRID VECTOR INDEX.

Here are some examples on how you can modify existing hybrid vector indexes:

• To rebuild all parts of a hybrid vector index:

  Use the following syntax to rebuild all parts of a hybrid vector index (both Oracle Text index and vector index) with the original preference settings:

  Syntax:

  ALTER INDEX index_name REBUILD [PARALLEL n];

  Note that you do not need to specify any PARAMETERS clause when rebuilding both parts of a hybrid vector index.

  Example:

  ALTER INDEX my_hybrid_idx REBUILD;
  
  SELECT (select id from doc_table where rowid = jt.doc_rowid) as doc,
         jt.chunk
  FROM JSON_TABLE(
           DBMS_HYBRID_VECTOR.SEARCH(
             json(
               '{ "hybrid_index_name" : "my_hybrid_idx",
                  "vector" : 
                   { "search_text"    : "vector based search capabilities",
                     "search_mode"    : "CHUNK"
                   },
                  "return" : 
                   { "topN"           : 10 }
               }')
             ),
             '$[*]' COLUMNS doc_rowid  PATH '$.rowid',
                            chunk      PATH '$.chunk_text') jt;

• To rebuild only the vector index part:

  Use the following syntax to rebuild only the vector index part of a hybrid vector index with the original preference settings:

  Syntax:

  ALTER INDEX index_name REBUILD 
    PARAMETERS('UPDATE VECTOR INDEX') [PARALLEL n];

  Example:

  ALTER INDEX my_hybrid_idx REBUILD 
    PARAMETERS('UPDATE VECTOR INDEX') PARALLEL 3;
  
  SELECT (select id from doc_table where rowid = jt.doc_rowid) as doc,
         jt.chunk
  FROM JSON_TABLE(
           DBMS_HYBRID_VECTOR.SEARCH(
             json(
               '{ "hybrid_index_name" : "my_hybrid_idx",
                  "vector" : 
                   { "search_text"    : "vector based search capabilities",
                     "search_mode"    : "CHUNK"
                   },
                  "return" : 
                   { "topN"           : 10 }
               }')
             ),
             '$[*]' COLUMNS doc_rowid  PATH '$.rowid',
                            chunk      PATH '$.chunk_text') jt;