Enforcing currency and consistency constraints in database query processing
    1.
    发明申请
    Enforcing currency and consistency constraints in database query processing 有权
    在数据库查询处理中强制执行货币和一致性限制

    公开(公告)号:US20050210010A1

    公开(公告)日:2005-09-22

    申请号:US10805083

    申请日:2004-03-19

    IPC分类号: G06F7/00 G06F17/30

    CPC分类号: G06F17/30522

    摘要: Currency and consistency requirements are specified as part of a query against a database that may contain replicated data that is updated asynchronously and therefore may not be completely up to date. The database system constructs query execution plans that include an input selection operator that verifies the currency of a replica and selects a subplan using the replica for execution only when the replica meets the query's currency constraints. It checks possible query execution plans at construction time against the query's consistency constraints and any plans that may produce a result not meeting the consistency constraints are rejected. In this way, the query result is guaranteed to satisfy the query's currency and consistency requirements.

    摘要翻译: 货币和一致性要求被指定为针对数据库的查询的一部分,数据库可能包含异步更新的复制数据,因此可能不完全是最新的。 数据库系统构建查询执行计划,其中包括验证副本的货币的输入选择运算符,并且只有当副本符合查询的货币约束时才使用副本才能执行子计划。 它可以根据查询的一致性约束在施工时检查可能的查询执行计划,并且拒绝可能产生不符合一致性约束的结果的任何计划。 以这种方式,查询结果保证满足查询的货币和一致性要求。

    Enforcing currency and consistency constraints in database query processing
    2.
    发明授权
    Enforcing currency and consistency constraints in database query processing 有权
    在数据库查询处理中强制执行货币和一致性限制

    公开(公告)号:US07739262B2

    公开(公告)日:2010-06-15

    申请号:US10805083

    申请日:2004-03-19

    IPC分类号: G06F17/30

    CPC分类号: G06F17/30522

    摘要: Currency and consistency requirements are specified as part of a query against a database that may contain replicated data that is updated asynchronously and therefore may not be completely up to date. The database system constructs query execution plans that include an input selection operator that verifies the currency of a replica and selects a subplan using the replica for execution only when the replica meets the query's currency constraints. It checks possible query execution plans at construction time against the query's consistency constraints and any plans that may produce a result not meeting the consistency constraints are rejected. In this way, the query result is guaranteed to satisfy the query's currency and consistency requirements.

    摘要翻译: 货币和一致性要求被指定为针对数据库的查询的一部分,数据库可能包含异步更新的复制数据,因此可能不完全是最新的。 数据库系统构建查询执行计划,其中包括验证副本的货币的输入选择运算符,并且只有当副本符合查询的货币约束时才使用副本才能执行子计划。 它可以根据查询的一致性约束在施工时检查可能的查询执行计划,并且拒绝可能产生不符合一致性约束的结果的任何计划。 以这种方式,查询结果保证满足查询的货币和一致性要求。