COMPUTER SCIENCE AND ENGINEERING
SQL
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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The SQL ALTER TABLE clause modifies a table definition by altering, adding, or deleting table columns and/or constraints
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The SQL ALTER TABLE clause is used to insert data into database table
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THE SQL ALTER TABLE deletes data from database table
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The SQL ALTER TABLE clause is used to delete a database table
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Detailed explanation-1: -d) The SQL ALTER TABLE clause is used to delete a database table. Explanation: The ALTER TABLE statement is used to add, delete, or modify columns. Check this: Information Technology Books | Programming MCQs. 6.
Detailed explanation-2: -The ALTER TABLE statement is used to add, delete, or modify columns in an existing table. The ALTER TABLE statement is also used to add and drop various constraints on an existing table.
Detailed explanation-3: -Use the MODIFY clause to change the data type, length, or default value of a column, to add or remove the security label of a column, to allow or disallow NULL values in a column, or to reset the serial counter of a SERIAL, SERIAL8, or BIGSERIAL column. This syntax fragment is part of the ALTER TABLE statement.
Detailed explanation-4: -The ALTER command in SQL is used to make changes to a table, view, or the entire database. We can add, modify, and drop constraints, columns, and indexes using the ALTER command in SQL.
Detailed explanation-5: -The simplest way to rename a column is to use the ALTER TABLE command with the RENAME COLUMN clause.