SQL AND & OR Operators
The AND & OR operators are used to filter records based on more than one
condition.
The AND & OR Operators
The AND operator displays a record if both the first condition and the second
condition is true.
The OR operator displays a record if either the first condition or the second
condition is true.
AND Operator Example
The "Persons" table:
| P_Id |
LastName |
FirstName |
Address |
City |
| 1 |
Hansen |
Ola |
Timoteivn 10 |
Sandnes |
| 2 |
Svendson |
Tove |
Borgvn 23 |
Sandnes |
| 3 |
Pettersen |
Kari |
Storgt 20 |
Stavanger |
Now we want to select only the persons with the first name equal to "Tove"
AND the last name equal to "Svendson":
We use
the following SELECT
statement:
SELECT * FROM Persons
WHERE FirstName='Tove'
AND LastName='Svendson' |
The result-set will look like this:
| P_Id |
LastName |
FirstName |
Address |
City |
| 2 |
Svendson |
Tove |
Borgvn 23 |
Sandnes |
OR Operator Example
Now we want to select only the persons with the first name equal to "Tove"
OR the first name equal to "Ola":
We use
the following SELECT
statement:
SELECT * FROM Persons
WHERE FirstName='Tove'
OR FirstName='Ola' |
The result-set will look like this:
| P_Id |
LastName |
FirstName |
Address |
City |
| 1 |
Hansen |
Ola |
Timoteivn 10 |
Sandnes |
| 2 |
Svendson |
Tove |
Borgvn 23 |
Sandnes |
Combining AND & OR
You can also combine AND and OR (use parenthesis to form complex
expressions).
Now we want to select only the persons with the last name equal to "Svendson"
AND the first name equal to "Tove"
OR to "Ola":
We use
the following SELECT
statement:
SELECT * FROM Persons WHERE
LastName='Svendson'
AND (FirstName='Tove' OR FirstName='Ola') |
The result-set will look like this:
| P_Id |
LastName |
FirstName |
Address |
City |
| 2 |
Svendson |
Tove |
Borgvn 23 |
Sandnes |
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