Methods, apparatus, and systems for a self-building hierarchically indexed multimedia database are disclosed. The database includes multiple branches categorizing industries. Each branch supports at least one node tree associated with at least one issuer entity and stores multimedia content associated with the at least one issuer entity. A first pattern is extracted from a first node tree supported by a first branch using a machine learning module trained based on the database. A second pattern is extracted from a second node tree supported by a second branch. The first node tree includes at least one node more than the second node tree. It is determined that the first pattern matches the second pattern using the machine learning module. The machine learning module is trained to compare two patterns extracted from the database. A new node corresponding to the at least one node is incorporated within the second node tree.