<https://mariadb.org/#/schema/person/image/>
<http://schema.org/url>
<https://secure.gravatar.com/avatar/39b623a1559cf9c69ac3d9d4fb44e7fe?s=96&d=mm&r=g>
<https://mariadb.org/duel-gdb-vs-linked-lists-trees-hash-tables/>