Abstract: Disclosed herein are system, method, and computer program product embodiments for distributed transaction processing in massively parallel processing (MPP) databases. An embodiment operates by receiving a transaction including a read timestamp corresponding to a version of data of a database associated with the query. It is determined whether a locally stored portion of the data of the database has a local timestamp that is equivalent to or after the read timestamp. A lock may be requested, and if received, the data is updated.

Abstract: Previously received queries from a search log are analyzed to determine a category of structured data associated with each query. For example, the categories may correspond to consumer product categories such as televisions, digital cameras, etc. For each category, the terms of the queries associated with the category are correlated with the attributes and attribute values of the structured data tuples associated with the category. The attributes may be ranked based on the correlation. When a subsequent query is received, the category of the query is determined and the ranked attributes associated with the category are used to select facets that are displayed to the user along with the search results.