Whenever "WHERE" condition clause guarantees that only one row would be returned Oracle optimizer chooses Index Unique Scans.
Index Unique Scans returns only 1 rowid.
Index Unique Scan is used when all columns of a unique (B-tree) index or an index created as a result of a primary key constraint are specified with equality conditions.
Index Unique Scans returns only 1 rowid.
Index Unique Scan is used when all columns of a unique (B-tree) index or an index created as a result of a primary key constraint are specified with equality conditions.
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