SQL SELECT Statement
The SELECT
statement is used to select data from a database.
The result is stored in a result table (called the result-set).
The syntax on the right is for the select statement:
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SELECT column_name(s)
FROM table_name;
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An SQL Select Example
Assume the table person
is given as follows:
person_id |
last_name |
first_name |
address |
city |
1 |
Hansen |
Ola |
Timoteivn 10 |
Sandnes |
2 |
Svendson |
Tove |
Borgvn 23 |
Sandnes |
3 |
Pettersen |
Kari |
Storgt 20 |
Stavanger |
To select the columns named
last_name
and
first_name
, use a select statement like this:
SELECT last_name, first_name FROM person;
LAST_NAME FIRST_NAME
--------------------------- ---------------------------
Hansen Ola
Svendson Tove
Pettersen Kari
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Select * Example
Now we want to select all the columns from the
person
table.
We use the following select statement:
SELECT * FROM person;
PERSON_ID LAST_NAME FIRST_NAME ADDRESS CITY
--------- ------------- -------------- ------------- -----------
1 Hansen Ola Timoteivn 10 Sandnes
2 Svendson Tove Borgvn 23 Sandnes
3 Pettersen Kari Storgt 20 Stavanger
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Demonstration
Below is an SQL test area from W3Schools, which uses the well-known Northwind sample database.
The tables here are for read only because of the problem of embedding the scripts.
For a fully working example, check this by using Chrome.
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The Database includes:
Tablename | Record |
Customers | 91 |
Categories | 8 |
Employees | 10 |
OrderDetails | 518 |
Orders | 196 |
Products | 77 |
Shippers | 3 |
Suppliers | 29 |
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This SQL-Statement is not supported in the WebSQL Database.
The example still works, because it uses a modified version of SQL.
Your browser does not support WebSQL.
Your are now using a light-version of the Try-SQL Editor, with a read-only Database.
If you switch to a browser with WebSQL support, you can try any SQL statement, and play with the Database as much as you like. The Database can also be restored at any time.
Our Try-SQL Editor uses WebSQL to demonstrate SQL.
A Database-object is created in your browser, for testing purposes.
You can try any SQL statement, and play with the Database as much as you like. The Database can be restored at any time, simply by clicking the "Restore Database" button.
W3C WebSQL
WebSQL stores a Database locally, on the user's computer. Each user gets their own Database object.
WebSQL Browser Support
WebSQL is supported in Chrome, Safari, and Opera.
If you use another browser you will still be able to use our Try SQL Editor, but a different version, using a server-based ASP application, with a read-only Access Database, where users are not allowed to make any changes to the data.