# SQL injection UNION attack, retrieving multiple values in a single column
Let's filter for `Accessories`.
Since we are proxying the traffic through Burp Suite, we can go to the `Proxy > HTTP History` tab to view this request.
Let's forward this request to the `Repeater` for further modification.
Once in the `Repeater`, let's set the `category` parameter to the following:
```
' UNION SELECT NULL--
```
Since the application returns an error, we know that the number of columns in the current query is more than 1. Let's set the `category` parameter to the following:
```
' UNION SELECT NULL,NULL--
```
Now that we know the current query has two columns, we can retrieve the usernames and password from the `username` and `password` columns respectively.
```
' UNION SELECT NULL,username||':'||password FROM users--
```
The `||` characters are used to concatenate strings together. So we are essentially dumping the username and password in the same column in the following format:
```
username:password
```
We can now login as the admin using the following credentials:
| Username | Password |
| ------------- | -------------------- |
| administrator | fq4yq6966ve3gff4iz65 |
We have solved the lab.
---
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```
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