Oracle OCP IZ0-053 Q14(? ?NLS_LENGTH_SEMANTICS)

471.Which of the following would be affected by setting NLS_LENGTH_SEMANTICS=CHAR?
A. All objects in the database
B. Tables owned by SYS and SYSTEM
C. Data dictionary tables
D. NCHAR columns
E. CHAR columns
Answer: E


http://docs.oracle.com/cd/B19306_01/server.102/b14237/initparams127.htm#REFRN10124

NLS_LENGTH_SEMANTICS enables you to create CHAR and VARCHAR2 columns using either byte or character length semantics. Existing columns are not affected.
NCHAR, NVARCHAR2, CLOB, and NCLOB columns are always character-based. You may be required to use byte semantics in order to maintain compatibility with existing applications.
NLS_LENGTH_SEMANTICS does not apply to tables in SYS and SYSTEM. The data dictionary always uses byte semantics.

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