java - is there any possibility to maintain 5 latest versions of major file in MySql Db? -

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subject::::is there possibility maintain 5 latest versions of major file in mysql db?

according proj req't need maintain latest 5 versions of file in mysql db, if version count reached 6 i've delete first version of file automatically..

is there path achieve requirement if plz me .thanks in advance

assuming store file in data column, can add versions_back column, , use in update , delete statements, this:

table structure:

id versions_back data <other columns> -- ------------- ---- --------------- 10       0       .... .... 12       1       .... .... 13       2       .... .... 15       3       .... .... 17       4       .... ....

performing insertion:

update versioned_file set versions_back=versions_back+1 insert versioned_file(data, versions_back) values (<file-data>, 0) delete versioned_file versions_back >= 5

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