Abstract: Aspects of the disclosure are directed to protecting non-public data used in computer-based trials. Reports can be generated based on the computer-based trials that contain performance metrics or other data points to evaluate the computer-based trials. The reports can be viewed by data providers and/or trial providers without divulging the non-public data. Data providers can provide the non-public data for running the computer-based trials. Trial providers can run the computer-based trials. A cloud provider can provide infrastructure for storing source code for the computer-based trials, the non-public data, and reports generated from the computer-based trials. The cloud provider can also provide infrastructure for executing the computer-based trials and generating the reports from the computer-based trials.

Abstract: Systems and methods here include computerized handling of database transactions that can be employed on distributed architecture without requiring a single point of synchronization. Thus, examples can be embodied by a combination of algorithms that can be implemented in software and hardware allowing distributed deployment on the software. Such systems may be used for updating several documents within a single transaction which may provide, for example, atomicity, consistency, isolation and/or durability of such transactions. This may be accomplished by ensuring a distributed consensus within any of various database nodes, while requiring only a majority of nodes handling each individual shards to be available for transactions to complete successfully.

Abstract: A hybrid-sharded index includes document-sharded posting lists and term-sharded posting lists. Implementations include systems and methods for updating a hybrid-sharded index. For example, a method may include receiving updates to the hybrid-sharded index and generating, at a first leaf node, replacement posting lists and change information for a respective second leaf node. The method may also include dividing the replacement posting lists into portions, a portion having associated change information and being associated with a respective one of the second leaf nodes and sending the portions to respective leaf nodes. At a particular leaf node of the second leaf nodes, the method includes merging a received portion into an updated posing list portion, swapping the updated posting list portion into memory. During the swap, the change information and the updated posting list portion are used to respond to a query with an older version of the hybrid-sharded index.

Abstract: A hybrid-sharded index includes document-sharded posting lists and term-sharded posting lists. Implementations include systems and methods using a distributed hybrid-sharded index. For example, a method may include receiving, at a root node, a query having a first term and a second term and determining, that the first term is term-sharded. The method may also include retrieving a term-sharded posting list for the first term from a first leaf node that stores the term-sharded posting list and determining, at the root node, a second leaf node that stores a document-sharded posting list for the second term. The method may include sending the second term and a sub-set of documents from the term-sharded posting list to the second leaf node, the sub-set being documents assigned to the second leaf node; and generating a search result using a response received from the second leaf node.