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This persistence model is the default. To allow a complex data types to be persisted, the content item is serialized and stored in a field in a standard database record. Metadata about what type of object is stored, what url variable values it is associated with, versioning etc is also recorded. The The container for Content Persistence is calledcalled ContentItem and it represents the fields in this database record.
The main disadvantage with this method is that it makes it difficult to efficiently find data related to the content item. The simplest method for avoiding this restriction is to use the SummaryCache module which removes this problem by caching summaries for all content items in memory.
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