Ohio Revised Code Title XXIX. Crimes Procedure § 2937.09

If the charge is a felony, the court or magistrate shall, before receiving a plea of guilty, advise the accused that such plea constitutes an admission which may be used against him at a later trial. If the defendant enters a written plea of guilty or, pleading not guilty, affirmatively waives the right to have the court or magistrate take evidence concerning the offense, the court or magistrate forthwith and without taking evidence may find that the crime has been committed and that there is probable and reasonable cause to hold the defendant for trial pursuant to indictment by the grand jury, and, if the offense is bailable, require the accused to enter into recognizance in such amount as it determines to appear before the court of common pleas pursuant to indictment, otherwise to be confined until the grand jury has considered and reported the matter.