两种方式 嵌套和父子关联
Nested
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Nested docs are stored in the same Lucene block as each other, which helps read/query performance. Reading a nested doc is faster than the equivalent parent/child.
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Updating a single field in a nested document (parent or nested children) forces ES to reindex the entire nested document. This can be very expensive for large nested docs
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"Cross referencing" nested documents is impossible
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Best suited for data that does not change frequently
Parent/Child
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Children are stored separately from the parent, but are routed to the same shard. So parent/children are slightly less performance on read/query than nested
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Parent/child mappings have a bit extra memory overhead, since ES maintains a "join" list in memory
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Updating a child doc does not affect the parent or any other children, which can potentially save a lot of indexing on large docs
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Sorting/scoring can be difficult with Parent/Child since the Has Child/Has Parent operations can be opaque at times
综上所述,两种方式均有利弊,官方建议,自己处理关联关系,减轻ES的压力。
本文转自whk66668888 51CTO博客,原文链接:http://blog.51cto.com/12597095/1904058