Why `table` can't be retrived?

A table is created, but can’t get the object by id in explorer or graphql, why?

open sui explorer with 0xca930370aa2d65ee60de7358be0126a43266cc25a9a99b8ba6e2c60d30e38ce6, then copy id from table, try to retrieve the table. I thought any object with an uid can be retrieved, am I correct?

When an object is wrapped inside another it becomes part of the object-data and not directly accessible from the global-storage. The way to store something under an object and still have it accessible from global-storage is dynamic fields. The table itself uses dynamic fields for its entries.
This means although the wrapped table is not accessible by id in the explorer, its entries are.

Thank you, I am able to retrieve all entries from a wrapped table using suix_getDynamicFields, but I couldn’t find any equivalent graphql query.

You should use the owner query instead of object: Example in testnet:

{
    owner(address: "0x6aa2467d2638f9234cb32ab8952e31ff59e002a4271c31dff94753dba23bdb26") {
        dynamicFields(first: 2) {
            pageInfo {
                hasNextPage
                endCursor
            }
            nodes {
                name {
                    json
                }
                value {
                    ... on MoveValue {
                        json
                    }
                }
            }
        }
    }
}