Updating data stored in a dispersed storage network

A dispersed storage (DS) module comprises:

• a first module, when operable within a computing device, causes the computing device to:
• receive 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;
• a second module, when operable within the computing device, causes the computing device to map 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, add 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, determine 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, create a middle data segment of the second plurality of data segments based on a corresponding middle data segment of the plurality of data segments;
• a third module, when operable within the computing device, causes the computing device to:
• encode 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
• a fourth module, when operable within the computing device, causes the computing device to:
• overwrite the corresponding middle data segment with the encoded data segment in the DSN.