如何计算mysql中两个字母数字字符串之间的差异

Question

In the above picture stud_roll1 is the starting rollno and stud_roll2 is the ending
rollno.How can I calculate the between rollno. Ex: 16un01 is stud_roll1 and 16un04 is the ending rollno the result for my question is 16un01,16un02,16un03,16un04. How can I get the result?

Answer 1

Try with this:

SET @first_value = (SELECT SUBSTRING("16un01", 5,2));
SET @second_value = (SELECT SUBSTRING("16un04", 5,2));
SET @counter = @first_value;
WHILE @counter <= @second_value DO
    SELECT CONCAT("16un",LPAD(@counter,2,"0")) 16un;
    SET @counter = @counter + 1;
END WHILE;

I make a stored procedure on @first_value and @second_value you can obtain minimum and maximum (Obviously with a query), i divided the string and put into a value. On While I make the values for the range put in into a stored procedure and run it, the values will be 16un01, 16un02, 16un03, 16un04