26.4.3.27 The schema_redundant_indexes and x$schema_flattened_keys Views

The schema_redundant_indexes view displays indexes that duplicate other indexes or are made redundant by them. The x$schema_flattened_keys view is a helper view for schema_redundant_indexes.

In the following column descriptions, the dominant index is the one that makes the redundant index redundant.

The schema_redundant_indexes view has these columns:

• table_schema

  The schema that contains the table.

• table_name

  The table that contains the index.

• redundant_index_name

  The name of the redundant index.

• redundant_index_columns

  The names of the columns in the redundant index.

• redundant_index_non_unique

  The number of nonunique columns in the redundant index.

• dominant_index_name

  The name of the dominant index.

• dominant_index_columns

  The names of the columns in the dominant index.

• dominant_index_non_unique

  The number of nonunique columns in the dominant index.

• subpart_exists

  Whether the index indexes only part of a column.

• sql_drop_index

  The statement to execute to drop the redundant index.

The x$schema_flattened_keys view has these columns:

• table_schema

  The schema that contains the table.

• table_name

  The table that contains the index.

• index_name

  An index name.

• non_unique

  The number of nonunique columns in the index.

• subpart_exists

  Whether the index indexes only part of a column.

• index_columns

  The name of the columns in the index.