This paper recommends recovery methods for records deleted from PostgreSQL. This paper includes a description of PostgreSQL, which is the subject of this study. It also incorporates a layout of the pages and records relevant to data storage and the deletion tests and recovery algorithm used. When recovering deleted records, PostgreSQL data files, which contain a history of deleted records, are required. Also, a Hex editor is used, which can check the contents of data files. One can analyze each record’s header information by opening PostgreSQL data files with a Hex editor. Then, the analyzed header information from the records is checked. If it is deemed that there are deleted records, they can be extracted for recovery. If VACUUM, a record cleanup program offered by PostgreSQL, has been used for deletion, the records cannot be restored. In this study, it was possible to recover the deleted records of the PostgreSQL database in the damages caused by cybercrime. Recovered records can be used as legal evidence, which can benefit companies in a court situation. The benefit of being in a court situation helps protect the interests of the enterprise.

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