ORA-00987

Error: ORA-00987: missing or invalid username(s)

Causa: No username was specified in a GRANT statement or one of the specified usernames is invalid. Valid usernames must be specified following the keyword TO in a GRANT statement to define a user. A username must begin with a letter, consist only of alphanumeric characters and the special characters $, _, and #, and be less than or equal to 30 characters. If it contains other characters, it must be enclosed in double quotation marks. It may not be a reserved word.

Acción: Specify a valid username, or list of usernames, following the keyword TO in the GRANT statement.