Which of the following DROP statements is incorrect?
Explanation
We can not drop rows , we can only delete rows.
DROP ROW statement simply does not exist in SQL.
DROP INDEX statement is used to delete an index in a table.
DROP TABLE statement is used to drop an existing table in a database.
DROP DATABASE statement is used to drop an existing database in SQL schema.
Theory
  • SQL DROP INDEX, DROP TABLE, and DROP DATABASE

    Indexes, tables, and databases can easily be deleted/removed with the DROP statement.
    Read more: SQL DROP
  • The DROP INDEX Statement

    The DROP INDEX statement is used to delete an index in a table.
    DROP INDEX Syntax for MS Access:
    DROP INDEX index_name ON table_name
    DROP INDEX Syntax for MS SQL Server:
    DROP INDEX table_name.index_name
    DROP INDEX Syntax for DB2/Oracle:
    DROP INDEX index_name
    DROP INDEX Syntax for MySQL:
    ALTER TABLE table_name DROP INDEX index_name
    Read more: SQL DROP
  • The DROP TABLE Statement

    The DROP TABLE statement is used to delete a table.
    DROP TABLE table_name
    Read more: SQL DROP
  • The DROP DATABASE Statement

    The DROP DATABASE statement is used to delete a database.
    DROP DATABASE database_name
    Read more: SQL DROP
  • The TRUNCATE TABLE Statement

    What if we only want to delete the data inside the table, and not the table itself?
    Then, use the TRUNCATE TABLE statement:
    TRUNCATE TABLE table_name
    Read more: SQL DROP

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