> For the complete documentation index, see [llms.txt](https://simon-6.gitbook.io/simoncyber/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://simon-6.gitbook.io/simoncyber/portswigger-web-academy/sql-injection/lab-10.md).
# Lab 10
You can use the `CAST()` function to achieve this. It enables you to convert one data type to another. For example, imagine a query containing the following statement:
`CAST((SELECT example_column FROM example_table) AS int)`
Often, the data that you're trying to read is a string. Attempting to convert this to an incompatible data type, such as an `int`, may cause an error similar to the following:
`ERROR: invalid input syntax for type integer: "Example data"`
{% hint style="info" %}
Sometimes causing errors will allow you to see the query it uses
{% endhint %}