A computer implemented method for creating indices for a database having a plurality of documents each being associated with one or more keywords. The method includes the steps of: dividing the database into a plurality of subsets; separating the keywords into a plurality of keyword groups based upon modulo G of the hash value of the keyword for each subset; reading each document of each subset to create a first sub-index and writing same to a storage device of the computer; reading the first sub-indices to merge the first sub-indices into a second sub-index for each keyword group to write same to the storage device; and reading the second sub-indices from the storage device to merge the second sub-indices into an index for the database and write same on the storage device. A program and a system for creating indices are also provided.