Fellow monks, i'm seeking enlightment regarding the following:

i have items ("leaves") that can belong to one or more groups ("branches"), and every group can be in 0 or more groups.

my question is, how can i store this kind of data in a (mysql) table? what i'm doing right now, is simply using a "relationships" table, where every row either has a "TOP" or the corresponding row-id in its "son_of" column.
this is of course not quite optimal, if i have to re-contruct the whole branch leading to a given row, since i'd have to do e.g. 5 SELECTS for the re-construction of the branch of a leaf that has a depth of 5 (according to my very limited SQL-skills).

i could maybe store serialized objects or xml in my database, but really rather wouldn't because i need speed and portability.

thanks,

schweini

In reply to storing tree-like structures in tables by schweini

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