3 ms·
a key has multi-value, multi-key point to the same value. You can regard it as a efficient implementation of undirected graph. Relational DB can do it very we
by liuliu 17y ago
a key has multi-value, multi-key point to the same value.
You can regard it as a efficient implementation of undirected graph.
Relational DB can do it very well with something like:
create table image2tag (
varchar image,
varchar tag,
primary key (image, tag),
index (image),
index (tag)
);