A safe value for the oldest transaction ID for which the commit time can

be retrieved (first part of <option>-c</>) can be determined by looking

for the numerically smallest file name in the directory

<filename>pg_committs</> under the data directory. Conversely, a safe

<filename>pg_commit_ts</> under the data directory. Conversely, a safe

value for the newest transaction ID for which the commit time can be

retrieved (second part of <option>-c</>) can be determined by looking for

the numerically greatest file name in the same directory. As above, the