Abstract: Disclosed herein is a computer-implemented method of processing a query using a columnstore comprising a plurality of segments, the method comprising: receiving a query comprising a parameter; determining a key corresponding to the parameter; identifying a mapping structure, from a plurality of mapping structures, relating to said key, wherein each mapping structure corresponds to a respective segment of the columnstore; interrogating the identified mapping structure to determine a value corresponding to the key, wherein the value identifies an entry of an index table of a plurality of index tables that corresponds to the respective segment, wherein the entry of the index table identifies a row of the respective segment of the columnstore relating to the parameter; and retrieving data relating to the parameter from a data source based on data stored in the entry of the index table.

Abstract: Disclosed herein is a computer-implemented method of processing a query using a columnstore comprising a plurality of segments, the method comprising: receiving a query comprising a parameter; determining a key corresponding to the parameter; identifying a mapping structure, from a plurality of mapping structures, relating to said key, wherein each mapping structure corresponds to a respective segment of the columnstore; interrogating the identified mapping structure to determine a value corresponding to the key, wherein the value identifies an entry of an index table of a plurality of index tables that corresponds to the respective segment, wherein the entry of the index table identifies a row of the respective segment of the columnstore relating to the parameter; and retrieving data relating to the parameter from a data source based on data stored in the entry of the index table.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for restarting a query using a token. One of the methods includes receiving, by a computer from a requesting device, a query; determining, using a data storage system, a current result responsive to the query; generating, using the current result, a restart token that represents operations performed to determine a plurality of results responsive to the query including the current result responsive to the query and that can be used to determine a new result responsive to the query that was not included in the plurality of results responsive to the query; and providing, to the requesting device, a message that includes a) first data for the restart token that represents operations performed to determine the plurality of results responsive to the query and b) second data for the current result responsive to the query.

Abstract: Techniques described herein can accelerate change data capture determinations such as stream reads, which show changes made to a table between two points in time. Three distinct row bitests that mark deleted, updated, inserted, rows in micro-partitions can be added as metadata for the table. These bitsets can be generated during DML operations and then stored as metadata of the new partition generated by the DML operations. The bitsets can then be used to generate streams showing the changes in the table between two points in time (changes interval).

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for restarting a query using a token. One of the methods includes receiving, by a computer from a requesting device, a query; determining, using a data storage system, a current result responsive to the query; generating, using the current result, a restart token that represents operations performed to determine a plurality of results responsive to the query including the current result responsive to the query and that can be used to determine a new result responsive to the query that was not included in the plurality of results responsive to the query; and providing, to the requesting device, a message that includes a) first data for the restart token that represents operations performed to determine the plurality of results responsive to the query and b) second data for the current result responsive to the query.

Abstract: Techniques described herein can accelerate change data capture determinations such as stream reads, which show changes made to a table between two points in time. Three distinct row bitests that mark deleted, updated, inserted, rows in micro-partitions can be added as metadata for the table. These bitsets can be generated during DML operations and then stored as metadata of the new partition generated by the DML operations. The bitsets can then be used to generate streams showing the changes in the table between two points in time (changes interval).

Abstract: Disclosed herein is a computer-implemented method of processing a query using a columnstore comprising a plurality of segments, the method comprising: receiving a query comprising a parameter; determining a key corresponding to the parameter; identifying a mapping structure, from a plurality of mapping structures, relating to said key, wherein each mapping structure corresponds to a respective segment of the columnstore; interrogating the identified mapping structure to determine a value corresponding to the key, wherein the value identifies an entry of an index table of a plurality of index tables that corresponds to the respective segment, wherein the entry of the index table identifies a row of the respective segment of the columnstore relating to the parameter; and retrieving data relating to the parameter from a data source based on data stored in the entry of the index table.

Abstract: Disclosed herein is a computer-implemented method of processing a query using a columnstore comprising a plurality of segments, the method comprising: receiving a query comprising a parameter; determining a key corresponding to the parameter; identifying a mapping structure, from a plurality of mapping structures, relating to said key, wherein each mapping structure corresponds to a respective segment of the columnstore; interrogating the identified mapping structure to determine a value corresponding to the key, wherein the value identifies an entry of an index table of a plurality of index tables that corresponds to the respective segment, wherein the entry of the index table identifies a row of the respective segment of the columnstore relating to the parameter; and retrieving data relating to the parameter from a data source based on data stored in the entry of the index table.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for restarting a query using a token. One of the methods includes receiving, by a computer from a requesting device, a query; determining, using a data storage system, a current result responsive to the query; generating, using the current result, a restart token that represents operations performed to determine a plurality of results responsive to the query including the current result responsive to the query and that can be used to determine a new result responsive to the query that was not included in the plurality of results responsive to the query; and providing, to the requesting device, a message that includes a) first data for the restart token that represents operations performed to determine the plurality of results responsive to the query and b) second data for the current result responsive to the query.

Abstract: Disclosed herein is a computer-implemented method of processing a query using a columnstore comprising a plurality of segments, the method comprising: receiving a query comprising a parameter; determining a key corresponding to the parameter; identifying a mapping structure, from a plurality of mapping structures, relating to said key, wherein each mapping structure corresponds to a respective segment of the columnstore; interrogating the identified mapping structure to determine a value corresponding to the key, wherein the value identifies an entry of an index table of a plurality of index tables that corresponds to the respective segment, wherein the entry of the index table identifies a row of the respective segment of the columnstore relating to the parameter; and retrieving data relating to the parameter from a data source based on data stored in the entry of the index table.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for restarting a query using a token. One of the methods includes receiving, by a computer from a requesting device, a query; determining, using a data storage system, a current result responsive to the query; generating, using the current result, a restart token that represents operations performed to determine a plurality of results responsive to the query including the current result responsive to the query and that can be used to determine a new result responsive to the query that was not included in the plurality of results responsive to the query; and providing, to the requesting device, a message that includes a) first data for the restart token that represents operations performed to determine the plurality of results responsive to the query and b) second data for the current result responsive to the query.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for restarting a query using a token. One of the methods includes receiving, by a computer from a requesting device, a query; determining, using a data storage system, a current result responsive to the query; generating, using the current result, a restart token that represents operations performed to determine a plurality of results responsive to the query including the current result responsive to the query and that can be used to determine a new result responsive to the query that was not included in the plurality of results responsive to the query; and providing, to the requesting device, a message that includes a) first data for the restart token that represents operations performed to determine the plurality of results responsive to the query and b) second data for the current result responsive to the query.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for restarting a query using a token. One of the methods includes receiving, by a computer from a requesting device, a query; determining, using a data storage system, a current result responsive to the query; generating, using the current result, a restart token that represents operations performed to determine a plurality of results responsive to the query including the current result responsive to the query and that can be used to determine a new result responsive to the query that was not included in the plurality of results responsive to the query; and providing, to the requesting device, a message that includes a) first data for the restart token that represents operations performed to determine the plurality of results responsive to the query and b) second data for the current result responsive to the query.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for restarting a query using a token. One of the methods includes receiving, by a computer from a requesting device, a query; determining, using a data storage system, a current result responsive to the query; generating, using the current result, a restart token that represents operations performed to determine a plurality of results responsive to the query including the current result responsive to the query and that can be used to determine a new result responsive to the query that was not included in the plurality of results responsive to the query; and providing, to the requesting device, a message that includes a) first data for the restart token that represents operations performed to determine the plurality of results responsive to the query and b) second data for the current result responsive to the query.

Abstract: A method and system for transforming a query tree that includes more than one aggregator. The method includes identifying a first aggregator in the query tree, identifying a second aggregator that is located below the first aggregator in the query tree, and merging the second aggregator with the first aggregator to form a merged aggregator.

Abstract: A computerized system and method for transforming (formatting or aggregating) the results of a query into a hierarchical information stream, such as an eXtensible Markup Language (XML) data stream is disclosed. A database server receives a query and generates a rowset. A rowset processor, using the mode specified in the query, processes the rowset and query to generate the XML data stream. For the “auto1” mode, the rowset processor transforms a rowset into an XML data stream using primary-foreign key information specified in the query to determine nesting. For the “auto2” mode, the rowset processor transforms a rowset into an XML data stream using table ordering information included in the query to determine nesting. For the “explicit” mode, the rowset processor transforms a rowset into an XML data stream using the explicit organizational information specified in the query.