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id ordering-data
title Ordering Data
sidebar_label Ordering Data
sidebar_position 2
tags
html
web-development
document-structure
description In this tutorial, you will learn about the structure of an HTML document and how to create a basic HTML document.

📗 Ordering Data

Welcome to the Selecting Data module! This foundational learning path is designed to help you master the basics of querying data, particularly focusing on how to retrieve specific information from databases effectively.

📘 Creating SQL Table

In this tutorial, you'll learn how to interpret and use rows in a database table. Tables are essential to storing structured data, and each row in a table represents a unique item or record.

Each row of a table represents a new item.

Each column of a table represents a specific attribute of the data, such as id, name, or username. These columns define the type of information stored for each item in the table.

For example, consider a table named Friends. Below is how a simple table might look:

Task: Sort a table using the ORDER BY clause

Lesson Overview

After using ORDER BY, we specify the column by which we want to order the entries.
For example, to sort by the name column:

The first step in ordering table is the SELECT ORDER BY helps you to arrange data in readable form Here FROM specify the table we are selecting from ountries. Here the query is ordering the number by name/.

:::info
```sql title="Friends" | name | username | -----------|---------| Smith | 19 | Jones | 60 | Wilson | 25 | ``` 
  -- creating orders
SELECT * FROM patients
ORDER BY name;

  ```



  </TabItem>
  
  <TabItem value="how-git-works" label="Output">
| name              | age                  |
-------------------|--------------------------|
Smith       | 19    |
Jones       | 60        |
Wilson       | 25   |
  </TabItem>
</Tabs>


:::


### Example Practice 

> To query data from a table, use the FROM clause followed by the table's name.


For example, consider a table named `Friends`. Below is how a simple table might look:



  :::info
<Tabs>
<TabItem value="SQL Table" label="SQL Table">
```sql title="Friends"
| name    | gdp     |
|---------|---------|
| Greece  | 187.46  |
| Sweden  | 474.15  |
| Iceland | 21.6    |
| Germany | 3449.05 |

SELECT *
FROM countries
ORDER BY name;
  ```

  </TabItem>
  
  <TabItem value="how-git-works" label="Output">
| name    | gdp     |
|---------|---------|
| Germany | 3449.05 |
| Greece  | 187.46  |
| Iceland | 21.6    |
| Sweden  | 474.15  |

  </TabItem>
</Tabs>


:::



:::tip
When requesting data with SQL staments like SELECT, we say that we are making a query.
From helps in select the name col from
While not necessary but its a good practice to finish the sql queries with;


By following these best practices, ASC is the default sort ordering method followed.
:::

### 🔄 Arranging ORDERS BY with ASC , DESC

  :::info
  Ordering text properties like name is different when comparing to the age
  We can order items in asseding starting with smalest value or deceding. 
<Tabs>
<TabItem value="SQL Table" label="SQL Table">
```sql title="friends"
| name   | age |
|--------|-----|
| Smith  | 19  |
| Jones  | 60  |
| Wilson | 25  |

SELECT *
FROM patients
ORDER BY age ASC;

  ```

  </TabItem>
  
  <TabItem value="how-git-works" label="Output">
| name   | age |
|--------|-----|
| Smith  | 19  |
| Wilson | 25  |
| Jones  | 60  |

  </TabItem>
</Tabs>


:::

## 🧹 Selecting with `DESC`

For Text value it order by Alphabetically 
When arranging numerical value the item with smallest value in that coloumn comes first 

---

  :::info
<Tabs>
<TabItem value="SQL Table" label="SQL Table">
```sql title="Subscribers"
| name   | age |
|--------|-----|
| Smith  | 19  |
| Jones  | 60  |
| Wilson | 25  |

SELECT *
FROM patients
ORDER BY age DESC;

  ```

  </TabItem>
  
  <TabItem value="how-git-works" label="Output">
| name   | age |
|--------|-----|
| Jones  | 60  |
| Wilson | 25  |
| Smith  | 19  |


  </TabItem>
</Tabs>


:::




# ✅ What You Have Learned

This module covers essential concepts related to ordering data in SQL:

- **ORDER BY Clause**  
Learn how to sort query results based on one or more columns using the `ORDER BY` keyword.

- **Ascending Order** (ASC)  
Understand that SQL sorts in ascending order by default, which is the same as explicitly using `ASC`.

- **Descending Order** (DESC)  
Use the `DESC` keyword to sort results from highest to lowest or reverse alphabetical order.

- **Sort by Column Values**  
Practice sorting by numeric or text column values to organize data meaningfully.

---