Question

A meteorological department uses a table called Readings in a database to store minute-by-minute readings of daily temperature readings from a large number different locations. At midnight every day, a query is executed to compute the minimum, maximum and average temperatures at each location, and this data is stored in a separate table. After this the data in Readings is no longer needed and is deleted. Then the data collection for the next day starts.

Which of the following statements is the most appropriate (efficient) for deleting the data at the end of each day?

Answer 1

Answer:

For Deleting the data from a particular column of a table Update command is appropriate.

because it will delete only the data of the particular column from  table so that one can store new data and one will not create a table again and again with the same column name.

The query will be;

update table_name set column_name= null;