Which of the following modifications may not succeed?
A. Changing a column data type from char to date
B. Changing a column data type from numeric to char
C. Both of the above actions should succeed
D. Neither of the above actions will succeed
Answer: Option A
This Question Belongs to Database >> Database Redesign
Which of the following SQL statements are helpful in database redesign?
A. Correlated subqueries only
B. EXISTS/NOT EXISTS expressions only
C. Both of the above are helpful
D. None of the above are helpful
What SQL command can be used to delete columns from a table?
A. MODIFY TABLE TableName DROP COLUMN ColumnName
B. MODIFY TABLE TableName DROP ColumnName
C. ALTER TABLE TableName DROP COLUMN ColumnName
D. ALTER TABLE TableName DROP ColumnName
Database redesign is not terribly difficult if the:
A. database is structured.
B. database is well-designed.
C. database has no data.
D. database is relatively small.
Which SQL-92 standard SQL command can be used to change a table name?
A. RENAME TABLE
B. CHANGE TABLE
C. ALTER TABLE
D. None of the above is correct
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