A command that lets you change one or more fields in a record is

The command that lets you change one or more fields in a record is the UPDATE command in SQL (Structured Query Language). Here's a step-by-step guide on how to use it:

1. Open your SQL command line or interface.

2. To change a field in a record, you need to know which table the record is in. Let's say the table is called "Students" and you want to change the "Grade" field.

3. Use the UPDATE command followed by the name of the table. For example: UPDATE Students

4. Use the SET command followed by the field you want to change, an equals sign, and the new value. For example: SET Grade = 'A'

5. Finally, you need to specify which record(s) you want to update. You do this with the WHERE command followed by a condition that matches the record(s). For example: WHERE StudentID = 1

6. Put it all together, and your command looks like this: UPDATE Students SET Grade = 'A' WHERE StudentID = 1

7. Press Enter to execute the command.

Remember to replace "Students", "Grade", "A", and "1" with the name of your table, the field you want to change, the new value, and the ID of the record you want to update, respectively.