bitcoind – Where can I find a high performance search capabilities in a Bitcoin node implementation?

Where can I find a Bitcoin node implementation, which is capable of thousands of searches per minute, without degrading performance of the node?

I am aware of two Bitcoin node implementations.

I am looking for a BTC node implementation, which implements higher performance search capabilities, so I can search using syntax similar in capabiilty to SQL. I understand why LevelDB was chosen in the Bitcoin Core implementation (not sure what is used in the btcd implementation), but search performance does not stand up to my use case of executing thousands of searches (using bloom filters) per minute, as described here.

I have written a searchable database back-end using PostgreSQL, but its database must be pruned in order to archieve the high performance I require, which is not optimal. Thinking out loud, it seems like a NoSQL database like Cassandra, MongoDB, or the like might be better suited to this use case. But, I have not been able to find a Bitcoin implementation, which uses a NoSQL or comparable database.

With that that in mind, does anyone know of a Bitcoin, or altcoin, node, which meets my use case?