SQL SELECT Statement
This chapter will explain the SELECT and the SELECT * statements.
The 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.
SQL SELECT Syntax
SELECT column_name(s)
FROM table_name |
and
 Note: SQL is not case sensitive. SELECT is the same as select.
An SQL SELECT 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 the content of the columns named "LastName" and "FirstName" from the table above.
We use the following SELECT statement:
| SELECT LastName,FirstName FROM Persons |
The result-set will look like this:
| LastName |
FirstName |
| Hansen |
Ola |
| Svendson |
Tove |
| Pettersen |
Kari |
SELECT * Example
Now we want to select all the columns from the "Persons" table.
We use the following SELECT statement:
Tip: The asterisk (*) is a quick way of selecting all columns!
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 |
| 3 |
Pettersen |
Kari |
Storgt 20 |
Stavanger |
Navigation in a Result-set
Most database software systems allow navigation in the result-set with programming functions, like: Move-To-First-Record,
Get-Record-Content, Move-To-Next-Record, etc.
Programming functions like these are not a part of this tutorial. To learn about accessing data with function calls,
please visit our ADO tutorial or our PHP tutorial.
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