### Example: Install DemandTools V Release 5.37.1 on Linux

Source: https://knowledge.validity.com/s/articles/DemandTools-V-Release-Linux-installation-FAQ

This is an example of the installation command for DemandTools V Release 5.37.1, assuming the installer is located in the Downloads folder.

```bash
sudo dpkg -i Downloads/DemandToolsInstaller/DemandTools.5.37.1.deb
```

--------------------------------

### RegEx Example: Number Not Starting with Leading 0

Source: https://knowledge.validity.com/s/articles/Single-Table-Dedupe-Field-Rules

This regular expression ensures that a number in a text field does not start with a leading zero. It applies to numeric data within text fields.

```regex
^[1-9]\d*$
```

--------------------------------

### Example SPF Record Implementation

Source: https://knowledge.validity.com/s/articles/Do-all-domains-need-a-Sender-Policy-Framework-SPF-record?nocache=https%3A%2F%2Fknowledge.validity.com%2Fs%2Farticles%2FDo-all-domains-need-a-Sender-Policy-Framework-SPF-record%3Flanguage%3Den_US

This example shows how to implement the SPF record for a domain not used for sending email within the DNS TXT record.

```dns
email.yourdomain.com. IN TXT "v=spf1 -all"
```

--------------------------------

### Add Message Tags and Configuration Set Header

Source: https://knowledge.validity.com/s/articles/Integrating-Amazon-SES-with-Everest?language=en_US

This example shows how to add both message tags and the configuration set header to your emails. Ensure 'myConfigurationSet' matches your configuration set name.

```text
X-SES-MESSAGE-TAGS: tagName1=tagValue1, tagName2=tagValue2
X-SES-CONFIGURATION-SET: myConfigurationSet
From: sender@example.com
To: recipient@example.com
Subject: Subject
Content-Type: multipart/alternative;
```