The optimizer in Informix Extended Parallel Server (XPS) could use more than one index on each table in a query, and now Informix 11.7 can as well.

Informix Extended Parallel Server (XPS)中的优化器可以在一个查询中使用每个表上的多个索引，现在Informix 11.7也可以。

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The compilation of the query on the remote server and fetching of enough data to fill the ATQ buffer on all legs of the UNION will proceed in parallel.

查询在远程服务器上的编译，以及取足够的数据来填充union所有分支上的AT Q缓冲区，这两个过程是并行进行的。

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