多項選擇題

Which three statements correctly describe the functions and use of constraints? （）

A. Constraints provide data independence.
B. Constraints make complex queries easy.
C. Constraints enforce rules at the view level.
D. Constraints enforce rules at the table level.
E. Constraints prevent the deletion of a table if there are dependencies.
F. Constraints prevent the deletion of an index if there are dependencies.

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單項選擇題

Which is a valid CREATE TABLE statement?（）

A. CREATE TABLE EMP9$# AS (empid number(2));
B. CREATE TABLE EMP*123 AS (empid number(2));
C. CREATE TABLE PACKAGE AS (packid number(2));
D. CREATE TABLE 1EMP_TEST AS (empid number(2));

多項選擇題

Which two are character manipulation functions?（）

A. TRIM
B. REPLACE
C. TRUNC
D. TO_DATE
E. MOD
F. CASE

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Which three statements correctly describe the functions and use of constraints? （）

你可能感興趣的試題

Which is a valid CREATE TABLE statement?（）

Which two are character manipulation functions?（）

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