公开(公告)号：US10997148B2

公开(公告)日：2021-05-04

申请号：US17078437

申请日：2020-10-23

Applicant: Snowflake Inc.

Inventor： Istvan Cseri ,  Torsten Grabs ,  Thierry Cruanes ,  Subramanian Muralidhar ,  Benoit Dageville

IPC: G06F16/22 ,  G06F16/21 ,  G06F16/23

Abstract: The subject technology receives one or more requests to execute one or more requested transactions on a journal table of a database, the journal table comprising a snapshot and a log table. The subject technology, based on the one or more requests, inserts a new row into the log table for each requested transaction, each new row reflecting a corresponding requested transaction. The subject technology receives, after the one or more requested transactions have been executed, a second request to execute a second requested transaction on the journal table. The subject technology generates, prior to executing the second requested transaction, a second snapshot, the second snapshot comprising a second representation of data in the journal table after the one or more requested transactions have been executed, the second snapshot stored in a third micro-partition different than the first micro-partition and the second micro-partition.

公开(公告)号：US10990576B2

公开(公告)日：2021-04-27

申请号：US17078397

申请日：2020-10-23

Applicant: Snowflake Inc.

Inventor： Istvan Cseri ,  Torsten Grabs ,  Thierry Cruanes ,  Subramanian Muralidhar ,  Benoit Dageville

IPC: G06F16/22 ,  G06F16/21 ,  G06F16/23

Abstract: The subject technology defines a journal table of a database, the journal table comprising a snapshot and a log table, the snapshot comprising a representation of data in the journal table at a particular time, the log table comprising a listing of requested changes to the journal table since the particular time, the snapshot stored in a first micro-partition, the log table stored in a second micro-partition. The subject technology receives, after at least one first requested transaction has been executed, a request to execute a second requested transaction on the journal table. The subject technology generates, prior to executing the second requested transaction, a second snapshot, the second snapshot comprising a second representation of data in the journal table after the at least one first requested transaction has been executed, the second snapshot stored in a third micro-partition different than the first micro-partition and the second micro-partition.

公开(公告)号：US20210042282A1

公开(公告)日：2021-02-11

申请号：US17078397

申请日：2020-10-23

Applicant: Snowflake Inc.

Inventor： Istvan Cseri ,  Torsten Grabs ,  Thierry Cruanes ,  Subramanian Muralidhar ,  Benoit Dageville

IPC: G06F16/22 ,  G06F16/23 ,  G06F16/21

Abstract: The subject technology defines a journal table of a database, the journal table comprising a snapshot and a log table, the snapshot comprising a representation of data in the journal table at a particular time, the log table comprising a listing of requested changes to the journal table since the particular time, the snapshot stored in a first micro-partition, the log table stored in a second micro-partition. The subject technology receives, after at least one first requested transaction has been executed, a request to execute a second requested transaction on the journal table. The subject technology generates, prior to executing the second requested transaction, a second snapshot, the second snapshot comprising a second representation of data in the journal table after the at least one first requested transaction has been executed, the second snapshot stored in a third micro-partition different than the first micro-partition and the second micro-partition.

公开(公告)号：US20200334242A1

公开(公告)日：2020-10-22

申请号：US16842942

申请日：2020-04-08

Applicant: Snowflake Inc.

Inventor： Subramanian Muralidhar ,  Benoit Dageville ,  Thierry Cruanes ,  Nileema Shingte ,  Saurin Shah ,  Torsten Grabs ,  Istvan Cseri

IPC: G06F16/242 ,  G06F3/06 ,  G06F16/23 ,  G06F16/16 ,  G06F16/25 ,  G06F9/54 ,  G06F16/22

Abstract: Systems, methods, and devices for automated maintenance of external tables in database systems are disclosed. A method includes receiving, by a database platform, read access to content in an external data storage platform that is separate from the database platform. The method includes defining an external table based on the content in the external data storage platform. The method includes connecting the database platform to the external table such that the database platform has read access for the external table and does not have write access for the external table. The method includes generating metadata for the external table, the metadata comprising information about data stored in the external table. The method includes receiving a notification that a modification has been made to the content in the external data storage platform, the modification comprising one or more of an addition of a file, a deletion of a file, or an update to a file in a source location for the external table. The method includes refreshing the metadata for the external table in response to the modification being made to the content in the external data storage platform.

公开(公告)号：US20200334241A1

公开(公告)日：2020-10-22

申请号：US16841831

申请日：2020-04-07

Applicant: Snowflake Inc.

Inventor： Subramanian Muralidhar ,  Benoit Dageville ,  Thierry Cruanes ,  Nileema Shingte ,  Saurin Shah ,  Torsten Grabs ,  Istvan Cseri

IPC: G06F16/242 ,  G06F3/06 ,  G06F16/23 ,  G06F16/25 ,  G06F16/2453

Abstract: Systems, methods, and devices for querying over an external table are disclosed. A method includes connecting a database platform to an external table such that the database platform has read access for the external table and does not have write access for the external table. The method includes receiving a query comprising a predicate, the query directed at least to data in the external table. The method includes determining, based on metadata, one or more partitions in the external table comprising data satisfying the predicate. The method includes pruning, based on the metadata, all partitions in the external table that do not comprise any data satisfying the predicate. The method includes generating a query plan comprising a plurality of discrete subtasks. The method includes assigning, based on the metadata, the plurality of discrete subtasks to one or more nodes in an execution platform.

公开(公告)号：US20200334239A1

公开(公告)日：2020-10-22

申请号：US16385774

申请日：2019-04-16

Applicant: Snowflake Inc.

Inventor： Subramanian Muralidhar ,  Benoit Dageville ,  Thierry Cruanes ,  Nileema Shingte ,  Saurin Shah ,  Torsten Grabs ,  Istvan Cseri

IPC: G06F16/242 ,  G06F16/23 ,  G06F16/2453 ,  G06F16/25 ,  G06F3/06

Abstract: Systems, methods, and devices for querying over an external table are disclosed. A method includes connecting a database platform to an external table such that the database platform has read access for the external table and does not have write access for the external table. The method includes receiving a query comprising a predicate, the query directed at least to data in the external table. The method includes determining, based on metadata, one or more partitions in the external table comprising data satisfying the predicate. The method includes pruning, based on the metadata, all partitions in the external table that do not comprise any data satisfying the predicate. The method includes generating a query plan comprising a plurality of discrete subtasks. The method includes assigning, based on the metadata, the plurality of discrete subtasks to one or more nodes in an execution platform.

公开(公告)号：US10776340B2

公开(公告)日：2020-09-15

申请号：US16705424

申请日：2019-12-06

Applicant: Snowflake Inc.

Inventor： Istvan Cseri ,  Torsten Grabs ,  Benoit Dageville

IPC: G06F16/23 ,  G06F16/27 ,  G06F16/2455

Abstract: Systems, methods, and devices for tracking changes to database data. A method includes determining a change to be executed on a micro-partition of a table of a database and executing the change on the table by generating a new micro-partition that embodies the change. The method includes updating a table history that includes a log of changes made to the table, wherein each change in the log of changes includes a timestamp, and wherein updating the table history includes inserting the change into the log of changes.

公开(公告)号：US20200218714A1

公开(公告)日：2020-07-09

申请号：US16824676

申请日：2020-03-19

Applicant: Snowflake Inc.

Inventor： Torsten Grabs ,  Istvan Cseri ,  Benoit Dageville

IPC: G06F16/23 ,  G06F16/2455 ,  G06F16/22

Abstract: Systems, methods, and devices for tracking a series of changes to database data are disclosed. A method includes executing a transaction to modify data in a micro-partition of a table of a database by generating a new micro-partition that embodies the transaction. The method includes associating transaction data with the new micro-partition, wherein the transaction data comprises a timestamp when the transaction was fully executed, and further includes associating modification data with the new micro-partition that comprises an indication of one or more rows of the table that were modified by the transaction. The method includes joining the transaction data with the modification data to generate joined data and querying the joined data to determine a listing of intermediate modifications made to the table between a first timestamp and a second timestamp.

公开(公告)号：US20200142882A1

公开(公告)日：2020-05-07

申请号：US16705424

申请日：2019-12-06

Applicant: Snowflake Inc.

Inventor： Istvan Cseri ,  Torsten Grabs ,  Benoit Dageville

IPC: G06F16/23 ,  G06F16/27 ,  G06F16/2455

Abstract: Systems, methods, and devices for tracking changes to database data. A method includes determining a change to be executed on a micro-partition of a table of a database and executing the change on the table by generating a new micro-partition that embodies the change. The method includes updating a table history that includes a log of changes made to the table, wherein each change in the log of changes includes a timestamp, and wherein updating the table history includes inserting the change into the log of changes.