The question seeks the specific retention period for temporary felony warrants, which could vary and was not directly addressed in the question or provided reference. The reference to Lex Julia notes a 20-hour detainment for witnesses in ancient Roman law, which may not be relevant to modern felony warrant procedures.
The question pertains to the retention period that is specified for the recording of certain legal documents in a database, specifically referring to temporary felony warrants. An answer to the question requires specific legal knowledge regarding the retention period set for these warrants which could vary by jurisdiction. Neither the question nor the provided reference from Lex Julia clearly state the retention period for temporary felony warrants. However, the reference to Lex Julia, an ancient Roman law, which notes that witnesses could be detained for twenty hours to convict an adulterer caught in the act, gives historical context but likely does not directly apply to modern legal practices concerning the retention period for felony warrants. To provide an accurate answer, one would need current legal standards from the relevant legal authority or jurisdiction.