In this tutorial, you'll learn how to fetch data from database tables using the SQL SELECT statement. It covers the syntax of the SELECT statement, how to specify individual columns or retrieve all columns, and how to filter data using the WHERE clause.
What Is SQL SELECT Statement?
The SQL SELECT statement retrieves data from one or more tables in a database, allowing you to access the specific information you need easily. This statement is commonly used and is essential for efficient data retrieval. Using the SELECT statement, you can streamline your database queries and get the precise data you require.
SQL SELECT Statement Syntax
The basic syntax of the SQL SELECT statement is as follows:
SELECT field1, field2, ...
FROM database_table;
Here, field1
, field2
,... are the names of the columns from which you want to fetch data, and database_table
is the table name containing the data.
If you want to retrieve all columns from a table, you can use the *
asterisk sign.
SELECT *
FROM table_name;
SQL SELECT Statement Examples
Let's take a look at some SQL SELECT statement examples:
Example 1: Selecting Specific Columns
Let's suppose we have a table called Customers
with the following columns:
- CustomerID
- FirstName
- LastName
- Address
- City
- PostalCode
- Country
To select only the FirstName
and LastName
columns from the table, we can use the following SQL statement:
SELECT FirstName, LastName
FROM Customers;
The above select query will return a result set containing only the FirstName
and LastName
columns.
Example 2: Selecting All Columns
To select all columns from the Customers
table, we can use the following SQL statement:
SELECT *
FROM Customers;
The above select query will return a result set containing all columns from the Customers
table.
Example 3: Filtering Data Using WHERE Clause
Suppose we want to retrieve only those customers who are located in London. We can use the following SQL statement:
SELECT *
FROM Customers
WHERE City = 'London';
The above select query will return a result set containing all columns from the Customers
table where the value in the City
column is equal to 'London'
.
Conclusion
In this tutorial, You learned about the SQL SELECT statement and how to use it to retrieve data from a database. We covered its syntax, how to select specific columns or all columns, and how to filter data using the WHERE clause. You can retrieve the data you need from your database using these techniques.