SQL WHERE Clause

The WHERE clause is used to filter records.

The WHERE Clause 

The WHERE clause is used to extract only those records that fulfill a specified criterion.

SQL WHERE Syntax


SELECT column_name(s)
FROM table_name
WHERE column_name operator value


WHERE Clause Example
The "student" table:

Student _No
Student_Name
Address
Year_Study
Sex
Date_of_birth
Course_No
ST100
K.Ranjan
Kandy
1
Male
17/01/1988
C1
ST101
N.Kumanan
Jaffna
2
Male
15/12/1989
C2
ST102
S.Ranjini
Vavuniya
1
Female
17/01/1989
C1
ST103
K.Dias
Colombo
3
Male
22/07/1987
C1
ST104
A.Kavitha
Matara
3
Female
20/03/1985
C2
ST105
L.Lavanya
Galle
2
Female
22/04/1989
C2
ST106
G.Moorthy
Jaffna
2
Male
12/01/1986
C1
ST107
F.Nathan
Matara
2
Male
29/01/1990
C3
ST108
A.H.M.Akmal
Puttalam
1
Male
12/12/1990
C3
Now we want to select only the student living in the Address "Jaffna" from the table above.
We use the following SELECT statement:

SELECT*FROM student WHERE Address='Jaffna';

The result-set will look like this:

Student_No
Student_Name
Address
Year_Study
Sex
Date_of_birth
Course_No
ST101
N.Kumanan
Jaffna
2
Male
1989-12-15
C2
ST106
G.Moorthy
Jaffna
2
Male
1986-01-12
C1

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