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_IdLastNameFirstNameAddressCity
1HansenOlaTimoteivn 10Sandnes
2SvendsonToveBorgvn 23Sandnes
3PettersenKariStorgt 20Stavanger

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_IdLastNameFirstNameAddressCity
2SvendsonToveBorgvn 23Sandnes


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_IdLastNameFirstNameAddressCity
1HansenOlaTimoteivn 10Sandnes
2SvendsonToveBorgvn 23Sandnes


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_IdLastNameFirstNameAddressCity
2SvendsonToveBorgvn 23Sandnes

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