sql - Convert the students marks into respective grades

Sql - Convert the students marks into respective grades

To convert student marks into respective grades in SQL, you can use a CASE statement to evaluate the marks and assign corresponding grades. Below is an example query that demonstrates how you might structure this in a SELECT statement:

SELECT student_id, marks, CASE WHEN marks >= 90 THEN 'A' WHEN marks >= 80 THEN 'B' WHEN marks >= 70 THEN 'C' WHEN marks >= 60 THEN 'D' ELSE 'F' -- Grade 'F' for marks below 60 END AS grade FROM student_marks;

In this example:

  • student_id and marks are assumed to be the columns in your table (student_marks). Adjust them based on your actual table structure.
  • The CASE statement evaluates the value of the marks column and assigns a grade based on the specified conditions.
  • Adjust the grading criteria (90, 80, 70, 60) as needed for your grading scale.
  • The ELSE 'F' part handles cases where the marks are below 60, assigning a grade of 'F'.

Make sure to replace student_marks with your actual table name.

You can use this query in a SELECT statement or modify it for use in an UPDATE statement if you want to update the grades in the table.

Adjust the conditions and grading scale according to your specific requirements.

Examples

  1. Convert Marks to Grades: Using CASE Statement

    • Description: Demonstrates how to use a CASE statement to assign grades based on predefined score ranges.
    -- Code Implementation SELECT student_name, marks, CASE WHEN marks >= 90 THEN 'A' WHEN marks >= 80 THEN 'B' WHEN marks >= 70 THEN 'C' WHEN marks >= 60 THEN 'D' ELSE 'F' END AS grade FROM students;

  2. Convert Marks to Grades: Using IIF Function (for MS Access)

    • Description: Illustrates using the IIF function to conditionally assign grades based on predefined score ranges (for MS Access).
    -- Code Implementation SELECT student_name, marks, IIF(marks >= 90, 'A', IIF(marks >= 80, 'B', IIF(marks >= 70, 'C', IIF(marks >= 60, 'D', 'F')))) AS grade FROM students;

  3. Convert Marks to Grades: Using DECODE Function (for Oracle)

    • Description: Guides on using the DECODE function to assign grades based on predefined score ranges (for Oracle).
    -- Code Implementation SELECT student_name, marks, DECODE WHEN marks >= 90 THEN 'A' WHEN marks >= 80 THEN 'B' WHEN marks >= 70 THEN 'C' WHEN marks >= 60 THEN 'D' ELSE 'F' END AS grade FROM students;

  4. Convert Marks to Grades: Using Nested CASE Statements

    • Description: Shows how to use nested CASE statements for more complex grading criteria.
    -- Code Implementation SELECT student_name, marks, CASE WHEN marks >= 90 THEN 'A' WHEN marks >= 80 THEN 'B' WHEN marks >= 70 THEN 'C' ELSE CASE WHEN marks >= 60 THEN 'D' ELSE 'F' END END AS grade FROM students;

  5. Convert Marks to Grades: Using Custom Function

    • Description: Demonstrates creating a custom function to calculate grades based on predefined rules.
    -- Code Implementation CREATE FUNCTION CalculateGrade(marks INT) RETURNS CHAR(1) BEGIN IF marks >= 90 THEN RETURN 'A'; ELSEIF marks >= 80 THEN RETURN 'B'; ELSEIF marks >= 70 THEN RETURN 'C'; ELSEIF marks >= 60 THEN RETURN 'D'; ELSE RETURN 'F'; END IF; END; SELECT student_name, marks, CalculateGrade(marks) AS grade FROM students;

  6. Convert Marks to Grades: Using Ranges with BETWEEN

    • Description: Illustrates using the BETWEEN operator to check if marks fall within specific ranges.
    -- Code Implementation SELECT student_name, marks, CASE WHEN marks BETWEEN 90 AND 100 THEN 'A' WHEN marks BETWEEN 80 AND 89 THEN 'B' WHEN marks BETWEEN 70 AND 79 THEN 'C' WHEN marks BETWEEN 60 AND 69 THEN 'D' ELSE 'F' END AS grade FROM students;

  7. Convert Marks to Grades: Using Lookup Table

    • Description: Guides on using a lookup table to map score ranges to grades.
    -- Code Implementation CREATE TABLE GradeLookup ( MinScore INT, MaxScore INT, Grade CHAR(1) ); INSERT INTO GradeLookup VALUES (90, 100, 'A'), (80, 89, 'B'), (70, 79, 'C'), (60, 69, 'D'); SELECT s.student_name, s.marks, g.Grade FROM students s JOIN GradeLookup g ON s.marks BETWEEN g.MinScore AND g.MaxScore;

  8. Convert Marks to Grades: Using DENSE_RANK Function

    • Description: Shows how to use the DENSE_RANK function to assign grades based on percentiles.
    -- Code Implementation SELECT student_name, marks, CASE WHEN DENSE_RANK() OVER (ORDER BY marks DESC) = 1 THEN 'A' WHEN DENSE_RANK() OVER (ORDER BY marks DESC) = 2 THEN 'B' WHEN DENSE_RANK() OVER (ORDER BY marks DESC) = 3 THEN 'C' WHEN DENSE_RANK() OVER (ORDER BY marks DESC) = 4 THEN 'D' ELSE 'F' END AS grade FROM students;

  9. Convert Marks to Grades: Using GROUP BY and AVG Function

    • Description: Demonstrates using the GROUP BY clause and AVG function to assign grades based on average scores.
    -- Code Implementation SELECT student_name, AVG(marks) AS average_marks, CASE WHEN AVG(marks) >= 90 THEN 'A' WHEN AVG(marks) >= 80 THEN 'B' WHEN AVG(marks) >= 70 THEN 'C' WHEN AVG(marks) >= 60 THEN 'D' ELSE 'F' END AS grade FROM students GROUP BY student_name;

  10. Convert Marks to Grades: Using ROW_NUMBER Function

    • Description: Illustrates using the ROW_NUMBER function to assign grades based on a specified order.
    -- Code Implementation SELECT student_name, marks, CASE WHEN ROW_NUMBER() OVER (ORDER BY marks DESC) = 1 THEN 'A' WHEN ROW_NUMBER() OVER (ORDER BY marks DESC) = 2 THEN 'B' WHEN ROW_NUMBER() OVER (ORDER BY marks DESC) = 3 THEN 'C' WHEN ROW_NUMBER() OVER (ORDER BY marks DESC) = 4 THEN 'D' ELSE 'F' END AS grade FROM students;

More Tags

eclipse-classpath icons radians mozilla windows-7-x64 sd-card django-orm artifactory dirname fillna

More Programming Questions

More Pregnancy Calculators

More Transportation Calculators

More Livestock Calculators

More Internet Calculators