A method for managing data using writeable snapshots in a multi-versioned, distributed B-tree comprising nodes distributed over a plurality of servers, includes receiving a transaction request specifying a transaction type, the transaction having a transaction snapshot id, and determining the transaction type. If the transaction type is an update transaction, the method includes determining a node to update, which is defined by a node snapshot id, and if the transaction snapshot id is greater that the node snapshot id, the method copies the node and updates the copy to create a writeable snapshot, assigns the transaction snapshot id as a node snapshot id of the copy, and places a pointer from the node to the copy.