I am doing a migration from D7 to D8. Due to various issues in the initial site, I am doing content migration through CSV import rather than the direct drupal to drupal migration that's built in.
My content type has a Video Embed Field in it, which was throwing errors on migration unless it was filled. As such, I had to throw in a placeholder video URL for all nodes that didn't have the node filled.
Is there a way to (within drupal, or via a SQL query) programatically remove the field content from all nodes where the url is "youtube.com/myPlaceholderVideo"? All the content is in, but now I'm stuck with ~450 nodes with this placeholder URL.