![]() ![]() When the parallel servers are finished executing the statement, the query coordinator performs any portion of the work that cannot be executed in parallel. The parallel execution servers performs each operation in parallel if possible. The SQL statement is executed as a sequence of operations (a full table scan to perform a join on a nonindexed column, an ORDER BY clause, and so on). The query coordinator obtains the necessary number of parallel servers. The user session or shadow process takes on the role of a coordinator, often called the query coordinator. If parallel execution is chosen, then the following steps occur: Each SQL statement undergoes an optimization and parallelization process when it is parsed.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |