•It is possible
for two different SMILES to produce the same
hash number. This is termed a collision. The thor server uses standard computer science procedures to resolve these.
•If a non-SMILES
identifier is used to look up, the “cross-reference” yields the SMILES which is/are at the root of the page(s) with that identifier.
both the above cases a small number of disc accesses will be needed to retrieve the data.