Q:

What's the equivalent of JPA or JDBC for node? 

I'm pretty new to node, and I was wondering if there's any standard, open, API that could abstract me away from all the different database idiosyncrasies. 
Any link with tutorials or documentation would be pretty much welcome indeed. 

A:

There's not a "standard" db abstraction layer for Node, but take a look at Node-DBI which is open-source and maintained on GitHub.  There are probably others but this one has a good interface and several adapters already. 

A:

I think node-jdbc is a comprehensive module which is frequently being updated.  Its documents are accessible on github as well.