Shulou(Shulou.com)06/01 Report--

8 、 Examine the following statement:

SQL > ALTER TABLE SALES MODIFY CONSTRAINT compete for DISABLE VALIDATE

Which three statements are true?

A) Rows may be inserted into the table.

B) The competes with index is made unusable.

C) The competes for index is dropped.

D) The constraint is still enforced for updated rows.

E) The constraint is still enforced for inserted rows.

Answer:CDE

-- =

SQL > create table tt (id int primary key)

The table has been created.

SQL > desc dba_constraints

Is the name empty? Types

-

OWNER VARCHAR2 (60)

CONSTRAINT_NAME NOT NULL VARCHAR2 (30)

CONSTRAINT_TYPE VARCHAR2 (1)

TABLE_NAME NOT NULL VARCHAR2 (30)

SEARCH_CONDITION LONG

R_OWNER VARCHAR2 (60)

R_CONSTRAINT_NAME VARCHAR2 (30)

DELETE_RULE VARCHAR2 (9)

STATUS VARCHAR2 (8)

DEFERRABLE VARCHAR2 (14)

DEFERRED VARCHAR2 (9)

VALIDATED VARCHAR2 (13)

GENERATED VARCHAR2 (14)

BAD VARCHAR2 (3)

RELY VARCHAR2 (4)

LAST_CHANGE DATE

INDEX_OWNER VARCHAR2 (30)

INDEX_NAME VARCHAR2 (30)

INVALID VARCHAR2 (7)

VIEW_RELATED VARCHAR2 (14)

SQL > SELECT CONSTRAINT_NAME,CONSTRAINT_type from dba_constraints where table_name='TT'

CONSTRAINT_NAME C

SYS_C006993 P

SQL > alter table tt modify constraint SYS_C006993 disable validate

The table has changed.

SQL > SELECT CONSTRAINT_NAME,CONSTRAINT_type,status from dba_constraints where table_name='TT'

CONSTRAINT_NAME C STATUS

SYS_C006993 P DISABLED

SQL > SELECT CONSTRAINT_NAME,CONSTRAINT_type,status,validated from dba_constraints where table_name='TT'

CONSTRAINT_NAME C STATUS VALIDATED

SYS_C006993 P DISABLED VALIDATED

SQL > SELECT CONSTRAINT_NAME,CONSTRAINT_type,status,validated,index_name from dba_constraints where table_name='TT'

CONSTRAINT_NAME C STATUS VALIDATED

INDEX_NAME

-

SYS_C006993 P DISABLED VALIDATED

SQL > set linesize 120

SQL > SELECT CONSTRAINT_NAME,CONSTRAINT_type,status,validated,index_name from dba_constraints where table_name='TT'

CONSTRAINT_NAME C STATUS VALIDATED INDEX_NAME

SYS_C006993 P DISABLED VALIDATED

SQL > select index_name from dba_indexes where table_name='TT'

No rows selected

SQL > insert into tt values (1)

Insert into tt values (1)

*

An error occurred on line 1:

ORA-25128: tables with disable and validation constraints (XYS.SYS_C006993) cannot be inserted / updated / deleted

SQL >

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