As at the time of publishing this post, the contact-form-7-to-database-extension aka contact form db plugin is missing in the WordPress repository. According to the plugin author, WordPress removed it due to a security concern which he claims has been addressed.
While we await it to be relisted at wordpress.org, you can download contact form db plugin at github. Download the zip file and upload via the plugins page in your WordPress admin dashboard.
About Contact Form DB Plugin For WordPress
Contact Form DB is a WordPress plugin to save form submissions into a database. It saves contact form submissions to your WordPress database and provides an administration page and shortcodes to view and display the data.
By simply installing the plugin, it will automatically begin to capture form submissions from contact form 7 plugin, Fast Secure Contact Form (FSCF) plugin, JetPack Contact Form plugin, Gravity Forms plugin etc
It also allows users to export saved data to csv file and display the saved data in posts and pages.
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