SQL 面接の質問と回答
Test your skills through the online practice test: SQL Quiz Online Practice Test
質問 96. Which is the subset of SQL commands used to manipulate Oracle Database structures, including tables?
Data Definition Language (DDL).
役に立ちましたか？
コメントを追加
コメントを見る
質問 97. What is the use of DESC in SQL?
DESC has two purposes. It is used to describe a schema as well as to retrieve rows from table in descending order.
Explanation :
The query SELECT * FROM EMP ORDER BY ENAME DESC will display the output sorted on ENAME in descending order.
役に立ちましたか？
コメントを追加
コメントを見る
質問 98. What command is used to create a table by copying the structure of another table?
CREATE TABLE .. AS SELECT command
Explanation:
To copy only the structure, the WHERE clause of the SELECT command should contain a FALSE statement as in the following.
CREATE TABLE NEWTABLE AS SELECT * FROM EXISTINGTABLE WHERE 1=2;
If the WHERE condition is true, then all the rows or rows satisfying the condition will be copied to the new table.
役に立ちましたか？
コメントを追加
コメントを見る
質問 99. TRUNCATE TABLE EMP; DELETE FROM EMP; Will the outputs of the above two commands differ?
Both will result in deleting all the rows in the table EMP..
役に立ちましたか？
コメントを追加
コメントを見る
質問 100. What is the output of the following query SELECT TRUNC(1234.5678,-2) FROM DUAL;?
1200.
役に立ちましたか？
コメントを追加
コメントを見る
ユーザー評価で最も役立つ内容: