How does apache solr search recognize my changes by mysql query in my database
Solr maintains in own search index separated from the database. A process is required to index content from your database into Solr's index. Usually, this is done transparently by the Drupal Solr integration modules. These integrtions rely on usage of Drupal API for content changes. These API allow integration code to be executed on changes. This code will either index the change directly, or mark the content for re-indexation during the next cron run.

By accessing the database directly, you bypass Durpal's APIs and prevent the integration module to see your changes.

If this is a one off operation, you should be able to mark all content for re-indexation from the administration page of your Solr integration module.