From 0d95ff5a545e43a1f33b90be07e15561cd195a13 Mon Sep 17 00:00:00 2001 From: eiffel-org Date: Fri, 26 May 2017 12:08:01 +0000 Subject: [PATCH] Update wikipage Persistence, storage, and retrieval. (Signed-off-by:b-meyer). git-svn-id: https://svn.eiffel.com/eiffel-org/trunk@1829 abb3cda0-5349-4a8f-a601-0c33ac3a8c38 --- .../Persistence--storage--and-retrieval.wiki | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/documentation/17.01/solutions/basic-computing/eiffelbase/eiffelbase-tutorial/eiffelbase-kernel/Persistence--storage--and-retrieval.wiki b/documentation/17.01/solutions/basic-computing/eiffelbase/eiffelbase-tutorial/eiffelbase-kernel/Persistence--storage--and-retrieval.wiki index 48d337a6..56080b34 100644 --- a/documentation/17.01/solutions/basic-computing/eiffelbase/eiffelbase-tutorial/eiffelbase-kernel/Persistence--storage--and-retrieval.wiki +++ b/documentation/17.01/solutions/basic-computing/eiffelbase/eiffelbase-tutorial/eiffelbase-kernel/Persistence--storage--and-retrieval.wiki @@ -7,9 +7,11 @@ Most object-oriented applications need the ability to store object structures on A fundamental requirement on object persistence mechanisms is the ''Persistence Completeness'' rule, stated as follows in ''[[Eiffel: The Language]]'': -Whenever an object is stored into an external file, the stored content contains all the dependents of that object. Conversely, retrieving a previously stored object also retrieves all its dependents. - +
Whenever an object is stored into an external file, the stored content contains all the dependents of that object. Conversely, retrieving a previously stored object also retrieves all its dependents. +
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Storing an object just by itself would usually result in wrong semantics: most objects contain references to other objects, which must also be stored and retrieved with it. The persistence completeness rule ensures that this is always the case. It also means, of course, that features used for storing and retrieving objects must do much more than simple input and output; they must perform complete traversals of object structures. +
=Varieties of store operations=