The SELECT statement is used to select data from a database.
The data returned is stored in a result table, called the result-set.
SELECT Syntax
SELECT column1, column2, ...
FROM table_name; Here, column1, column2, … are the field names of the table you want to select data from. If you want to select all the fields available in the table, use the following syntax:
SELECT * FROM table_name; Demo Database
In this tutorial, we will use the well-known Northwind sample database.
Below is a selection from the “Customers” table in the Northwind sample database:
| CustomerID | CustomerName | ContactName | Address | City | PostalCode | Country |
|---|---|---|---|---|---|---|
| 1 | Alfreds Futterkiste | Maria Anders | Obere Str. 57 | Berlin | 12209 | Germany |
| 2 | Ana Trujillo Emparedados y helados | Ana Trujillo | Avda. de la Constitución 2222 | México D.F. | 05021 | Mexico |
| 3 | Antonio Moreno Taquería | Antonio Moreno | Mataderos 2312 | México D.F. | 05023 | Mexico |
| 4 | Around the Horn | Thomas Hardy | 120 Hanover Sq. | London | WA1 1DP | UK |
| 5 | Berglunds snabbköp | Christina Berglund | Berguvsvägen 8 | Luleå | S-958 22 | Sweden |
SELECT Columns Example
The following SQL statement selects the “CustomerName”, “City”, and “Country” columns from the “Customers” table:
Example
SELECT CustomerName, City, Country FROM Customers; SELECT * Example
The following SQL statement selects ALL the columns from the “Customers” table:
Example
SELECT * FROM Customers; The MySQL SELECT DISTINCT Statement
The SELECT DISTINCT statement is used to return only distinct (different) values.
Inside a table, a column often contains many duplicate values; and sometimes you only want to list the different (distinct) values.
SELECT DISTINCT Syntax
SELECT DISTINCT column1, column2, ...
FROM table_name; SELECT Example Without DISTINCT
The following SQL statement selects all (including the duplicates) values from the “Country” column in the “Customers” table:
Example
SELECT Country FROM Customers; Now, let us use the SELECT DISTINCT statement and see the result.
SELECT DISTINCT Examples
The following SQL statement selects only the DISTINCT values from the “Country” column in the “Customers” table:
Example
SELECT DISTINCT Country FROM Customers; The following SQL statement counts and returns the number of different (distinct) countries in the “Customers” table:
Example
SELECT COUNT(DISTINCT Country) FROM Customers;