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  • Oracle中可被并行化执行的SQL操作

    并不是所有的SQL operations都是可并行化的;不少人认为sort merge join这种排序合并操作是不能并行化的,这显示是一种错误的认识。有了这样一个列表你就可以更好地理解Oracle中的Parallel Execution了:
    Parallel Query:
    Table scan
    Nested loop join
    Sort merge join
    NOT IN
    GROUP BY
    Hash join
    SELECT DISTINCT
    UNION and UNION ALL
    Aggregation
    PL/SQL functions called from SQL
    ORDER BY
    
    DDL:
    CREATE TABLE AS SELECT
    CREATE INDEX
    Rebuild index
    Move partition
    Split partition
    
    DML:
    UPDATE   on partitioned table
    DELETE   on partitioned table
    MERGE    on partitioned table
    INSERT … SELECT
    Enable constraint (the table scan is parallelized)
    Star transformation
    
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  • 原文地址:https://www.cnblogs.com/macleanoracle/p/2967681.html
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