In some of my PDBs, I see indexes like below; the one with the comment "Index1" below with some BINARY_AI thing.
It is created on the primary key column. Are these indexes even useful ?
But, the primary key itself uses another index (PALLET_DETAIL_IDX2) to enforce the primary key.
--- Needless to say, it is a table with lots of columns in my real-life scenario
CREATE TABLE PALLET_DETAIL (PALLET_ID VARCHAR2(64 CHAR) NOT NULL);
-- Index1
CREATE UNIQUE INDEX PALLET_DETAIL_IDX1 ON PALLET_DETAIL(NLSSORT(PALLET_ID,'nls_sort=''BINARY_AI'''));
-- Index2
CREATE UNIQUE INDEX PALLET_DETAIL_IDX2 ON PALLET_DETAIL(PALLET_ID);
ALTER TABLE PALLET_DETAIL ADD (CONSTRAINT PALLET_DETAIL_PK PRIMARY KEY (PALLET_ID) USING INDEX PALLET_DETAIL_IDX2 ENABLE VALIDATE);