27.4.3.27 The schema_redundant_indexes and x$schema_flattened_keys Views

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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.

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Document created the 26/06/2006, last modified the 26/10/2018
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References

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