114. Which statements are true? (Choose all that apply.)
A. The data dictionary is created and maintained by the database
B. The data dictionary views can consist of joins of dictionary base tables
and user defined tables.
C. The usernames of all the users including the database administrators are
stored in the data dictionary.
D. The USER_CONS_COLUMNS view should be queried to find the names of the
columns to which a constraint applies.
E. Both USER_OBJECTS and CAT views provide the same information about all
the objects that are owned by the user.
F. Views with the same name but different prefixes, such as DBA, ALL and USER,
use the same base tables from the data dictionary
对应C的疑问: select * from v$pwfile_users; 目前只有sys用户,口令
oracle 超级用户口令放在文件里 ,好恢复 PWDosid.ora 可以删除的
sql server sa不是用户，是个登陆,里面有dbo用户 ,只是绑定了
There are only two columns in USER_CATALOG: TABLE_TYPE and TABLE_
NAME, where TABLE_NAME is actually the name of the table, view, sequence, or synonym
object.A synonym for USER_CATALOG is CAT.
The USER_OBJECTS view contains information about all objects owned by the user(包括
存储过程等). A synonym for USER_OBJECTS is OBJ.
The data dictionary is a collection of database tables and views. It is automatically
built and populated by the Oracle database. The information stored in the data
dictionary includes the full description of all the database objects you create as part
of your application: tables, views, indexes, constraints, synonyms, sequences, and
来自 “ ITPUB博客 ” ，链接：http://blog.itpub.net/11312660/viewspace-718922/，如需转载，请注明出处，否则将追究法律责任。