1. A method for data deduplication, the method comprising: obtaining a current file in the data; determining whether a similar historical file exists based on a sampled data block from at least one predetermined location in the current file, wherein the determining whether the similar historical file exists based on the sampled data block from at least one predetermined location in the current file comprises: determining a hash value of the sampled data block, mapping the hash value of the sampled data block to a preset corresponding location of a Bloom filter, and determining whether corresponding locations are all set, in response to determining that the corresponding locations are not all set: determining that a similar historical file does not exist, and updating the Bloom filter based on the hash value of the sampled data block, and in response to determining that the corresponding locations are all set: retrieving a first hash value table for a hash value matching the hash value of the sampled data block, and determining whether a similar historical file exists based on a statistical result of the matching, the first hash value table recording hash values of sampled data blocks of historical files at the predetermined location; in response to non-existence of the similar historical file, storing the current file and corresponding metadata on a file basis; and in response to existence of the similar historical file, applying a deduplication operation on the current file on a block basis.