为什么这个非常简单的xquery在sql server (存储在一列中的2mb xml文档)中执行需要10分钟,而在使用基于氧气/文件的查询时只需要14秒?
SELECT model.query('declare default element namespace "http://www.sbml.org/sbml/level2";
for $all_species in //species, $all_reactions in //reaction
where data($all_species/@compartment)="plasma_membrane" and $all_reactions/listOfReactants/speciesReference/@species=$all_species/@id
return <result>{data($all_species/@id)}</result>') from sbml;发布于 2010-03-27 20:09:38
"//“杀死MSSql,请使用尽可能精确的路径:http://scarydba.wordpress.com/2009/11/30/xquery-for-idiots/
发布于 2009-12-22 03:02:35
您的XML有模式声明吗?你在它上面放了合适的索引吗?
CREATE XML INDEX (Transact-SQL) CREATE XML SCHEMA COLLECTION (Transact-SQL)https://stackoverflow.com/questions/1941178
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