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单项选择题
A.
B.
C.
D.
E. The SQL statement produces an error.
单项选择题
A. SELECT TO_CHAR(SYSDATE,'yyyy') FROM dual;
B. SELECT TO_DATE(SYSDATE,'yyyy') FROM dual;
C. SELECT DECODE(SUBSTR(SYSDATE, 8), 'YYYY') FROM dual;
D. SELECT DECODE(SUBSTR(SYSDATE, 8), 'year') FROM dual;
E. SELECT TO_CHAR(SUBSTR(SYSDATE, 8,2),'yyyy') FROM dual;
单项选择题
A.All of the desired results
B.Two of the desired results
C.One of the desired results
D.An error statement
单项选择题
A. Create groups of data
B. Sort data in a specific order
C. Convert data to a different format
D. Retrieve data based on an unknown condition
单项选择题
A. WHERE
B. HAVING
C. RESTRICT
D. GROUP BY
E. ORDER BY
单项选择题
A.SELECT*FROMDEPT;
B.SELECT*FROMSCOTT.DEPT;
C.SELECT*FROMDBASCOTTDEPT;
D.SELECT*FROMALL_USERSWHEREUSER_NAME=';SCOTT';ANDTABLENAME=';DEPT';;
单项选择题
A. You can join a maximum of two tables through an equijoin.
B. You can join a maximum of two columns through an equijoin.
C. You specify an equijoin condition in the SELECT or FROM clauses of a SELECT statement.
D. To join two tables through an equijoin, the columns in the join condition must be primary key and foreign key columns.
E. You can join n tables (all having single column primary keys) in a SQL statement by specifying a minimum of n-1 join conditions.
多项选择题
A. A single row subquery can retrieve data from only one table.
B. A SQL query statement cannot display data from table B that is referred to in its subquery, unless table B is included in the main query's FROM clause.
C. A SQL query statement can display data from table B that is referred to in its subquery, without including table B in its own FROM clause.
D. A single row subquery can retrieve data from more than one table.
E. A single row subquery cannot be used in a condition where the LIKE operator is used for comparison.
F. A multiple-row subquery cannot be used in a condition where the LIKE operator is used for comparison.
单项选择题
A. MAX
B. MIN
C. SUM
D. COUNT
E. TOTAL
F. LARGEST