Comment by mti

Good point. Note however that PIR is a rather restricted form of search (e.g., with no privacy for the server), but even so, DEPIR has polylog(n) queries (not log n), and requires superlinear preprocessing and a polynomial blowup in the size of the database. I think recent concrete estimates are around a petabyte of storage for a database of 2^20 words. So as you say, pretty impractical.