When do you use the keyword FIELDS in an ABAP SELECT statement?

The keyword FIELDS is used in an ABAP SELECT statement to specify the list of fields that you want to retrieve from the database table. This keyword is typically placed after the FROM clause, where you define the data source from which you're selecting data. The use of FIELDS in this context explicitly indicates which fields are being selected, ensuring that they are clearly defined for retrieval.

Using FIELDS allows for greater clarity and structure in your SQL queries, especially when combined with other clauses such as WHERE, ORDER BY, or GROUP BY, which serve different purposes. Placing the FIELDS keyword after the FROM clause establishes a clear link between the source of the data and the specific fields being requested.

Other keywords listed in the choices, such as ORDER BY, GROUP BY, and UNION, serve different purposes in SQL statements. For instance, ORDER BY is used to sort the result set, GROUP BY is used to aggregate results based on specified fields, and UNION combines the results of two or more SELECT statements. These keywords do not pertain to the selection of fields from the database directly, which is why they are not appropriate placements for the FIELDS keyword.