The InnoDB engine has a feature
题目
The InnoDB engine has a feature known as clustered indexes. Which three statements are true about clustered indexes as used in InnoDB?（）
- A、A primary key must exist for creation of a clustered index
- B、A clustered index allows fulltext searching within InnoDB
- C、The first unique index is always used as a clustered index and not a primary key
- D、A clustered index provides direct access to a page containing row data
- E、If no indexes exist, a hidden clustered index is generated based on row IDs
- F、A primary key is used as a clustered index
- G、A clustered index is a grouping of indexes from different tables into a global index for faster searching
