New Release ACA-Developer Alibaba Developer Questions

Object ACL is an object-level (not bucket level) permission control mechanism. There are currently three levels of access rights: private, public-read, and public-read-write.

"Private" indicates that an object is a private resource, that is, only the owner of the object has read and write permissions on the object, and other users can read but have no permission to modify or delete the object.

If the permissions of an object are not set, the permissions of the object are inherited from the bucket.

You can set the ACL associated with an object by examining the X-OSS-Object-ACL header in the HEAD request, when making the PutObjectACL API call.

Add an index to a field that is frequently queried but does not frequently perform add, delete, or modify operations.

Applies indices to fields that contain many records.

table should not contain more than 6 indexed fields.

Apply indexing to fields of fixed length (preferably not long fields).

Adhere to the rightmost prefix principle when using composite indexes.