公开(公告)号：US11995080B1

公开(公告)日：2024-05-28

申请号：US18358402

申请日：2023-07-25

Applicant: Snowflake Inc.

Inventor： Dimitrios Tsirogiannis ,  Zhaohui Zhang

IPC: G06F16/2453

CPC classification number: G06F16/24537 ,  G06F16/24542 ,  G06F16/24549

Abstract: The subject technology receives a query, the query including a statement for performing a join operation on a first table and a second table. The subject technology executes, by an execution node using a generated query plan, the query. The subject technology performs, during execution of the query by the execution node, a runtime range pruning process. The subject technology determines a set of range sets for pruning, each range set including a set of columns from the first table, the set of columns being removed from undergoing a read operation as part of executing the query. The subject technology determines, based on a range bloom vector, a set of rows in a particular range set of the first table to avoid scanning in connection with the read operation. The subject technology performs the read operation based a remaining set of rows.

公开(公告)号：US11899648B2

公开(公告)日：2024-02-13

申请号：US17821581

申请日：2022-08-23

Applicant: Snowflake Inc.

Inventor： Chen Luo ,  Alexander Miller ,  William Waddington ,  Zhaohui Zhang

IPC: G06F16/23

CPC classification number: G06F16/2322 ,  G06F16/2365 ,  G06F16/2379

Abstract: The subject technology inserts, by a first transaction, a new version of an object, the first transaction including a first statement to perform an update operation to a row in a first table, the object corresponding to data in the row to be updated, the first statement including information comprising an object key associated with the object. The subject technology performs, by a second transaction, a range read, the range read including information indicating the object key. The subject technology receives a set of conflicting transactions from the range read. The subject technology determines that a conflict occurred between the first transaction and a third transaction from the set of conflicting transactions. The subject technology performs a restart of the first transaction in response to determining that the conflict occurred.

公开(公告)号：US20230315720A1

公开(公告)日：2023-10-05

申请号：US18326356

申请日：2023-05-31

Applicant: Snowflake Inc.

Inventor： Chen Luo ,  Alexander Miller ,  William Waddington ,  Zhaohui Zhang

IPC: G06F16/23 ,  G06F9/52

CPC classification number: G06F16/2379 ,  G06F9/524 ,  G06F16/2365

Abstract: The subject technology determines that a first visible version of a key is not one of a N number of newest versions of the key based on searching for the key in a regular space to locate the first visible version of the key. The subject technology performs a search of an undo space to locate a second visible version of the key. The subject technology determines whether the first visible version or the second visible version of the key is newer. The subject technology provides a newer version of the key between the first visible version and the second visible version of the key.

公开(公告)号：US11704305B1

公开(公告)日：2023-07-18

申请号：US17649737

申请日：2022-02-02

Applicant: Snowflake Inc.

Inventor： Chen Luo ,  Alexander Miller ,  William Waddington ,  Zhaohui Zhang

IPC: G06F16/23 ,  G06F9/52

CPC classification number: G06F16/2379 ,  G06F9/524 ,  G06F16/2365

Abstract: The subject technology performs a search for a key in a regular space to locate a first visible version of the key. The subject technology determines that the first visible version of the key is not one of a N number of newest versions of the key. The subject technology performs a search of an undo space to locate a second visible version of the key. The subject technology determines whether the first visible version or the second visible version of the key is newer. The subject technology provides a newer version of the key between the first visible version and the second visible version of the key.

公开(公告)号：US11436212B2

公开(公告)日：2022-09-06

申请号：US17454368

申请日：2021-11-10

Applicant: Snowflake Inc.

Inventor： Chen Luo ,  Alexander Miller ,  William Waddington ,  Zhaohui Zhang

IPC: G06F16/23

Abstract: The subject technology inserts, by a first transaction, a new version of an object, the inserting corresponding to a first statement from the first transaction, the first statement including information indicating a first key, a first transaction identifier, a first statement number, and a first restart count. The subject technology performs, by a second transaction, a range read, the range read including information indicating the first key. The subject technology receives, after performing the range read, a set of conflicting transactions. The subject technology determines that a conflict occurred between the first transaction and a third transaction from the set of conflicting transactions.