1. A method comprises: receiving a modified data object for storage in a dispersed storage network (DSN), wherein the modified data object is a modified version of a data object and wherein the data object is divided into a plurality of data segments that is encoded using a dispersed storage error coding function and stored in the DSN; mapping portions of the modified data object to the plurality of data segments that includes: when a portion of the portions of the modified data object maps to a data segment of the plurality of data segments, adding the data segment to a second plurality of data segments for the modified data object; when another portion of the portions of the modified data object does not map to one of the plurality of data segments, determining whether the another portion corresponds to beginning data, middle data, or ending data of the modified data object; and when the another portion corresponds to the middle data of the modified data object, creating a middle data segment of the second plurality of data segments based on a corresponding middle data segment of the plurality of data segments; encoding the middle data segment of the second plurality of data segments using the dispersed storage error coding function to produce an encoded data segment; and overwriting the corresponding middle data segment with the encoded data segment in the DSN.