Functions in SQL

Differentiate between count() and count(*) functions in SQL with appropriate examples.

Predict the output of the code given below:

s="welcome2cs" 

n = len(s)
m=""
for i in range(0, n):
       if (s[i] >= 'a' and s[i] <= 'm'):
            m = m +s[i].upper()
 elif (s[i] >= 'n' and s[i] <= 'z'):
          m = m +s[i-1]
 elif (s[i].isupper()):
     m = m + s[i].lower()
 else:
     m = m +'&'
print(m)

Write the outputs of the SQL queries based on the relations Teacher and Placement given below:

Table: Teacher

Table: Placement

1. SELECT Department, avg(salary) FROM Teacher GROUP BY Department;
2. SELECT MAX(Date_of_Join), MIN(Date_of_Join) FROM Teacher;
3. SELECT Name, Salary, T.Department, Place FROM Teacher T, Placement P WHERE T.Department = P.Department AND Salary>20000;
4. SELECT Name, Place FROM Teacher T, Placement P WHERE Gender = ’F’ AND T.Department = P.Department;

Which function is used to display the total number of records from a table in a database?

Site any two differences between Single Row Functions and Aggregate Functions.

Write the name of the functions to perform the following operation:

To display your name in capital letters.

Write the output produced by the following SQL statement:

SELECT ROUND(342.9234, -1);

Write the name of the functions to perform the following operation:

To display the day like “Monday”, and “Tuesday”, from the date when India got independence.