Ga. Code § 17-7-190
When any person accused of a criminal offense before a court of inquiry is bound over or committed for trial in superior court, the judicial officer holding the court of inquiry shall, at the time of the commitment hearing, give a subpoena to all material witnesses examined for the state to appear and testify before the grand jury at the term to which the defendant is committed or bound to appear; and, after the hearing and commitment or binding over, the prosecutor may apply to the clerk of the superior court and obtain a subpoena for any person deemed by him to be a material witness for the state before the grand jury. The subpoenas issued under this Code section shall be effectual in compelling the attendance of the witnesses to appear and give evidence before the grand jury. The judicial officer holding the court of inquiry and the clerk of the superior court shall, on the first day of the term of court to which the defendant is committed or bound to appear, furnish the prosecuting officers with a complete list of all persons so subpoenaed.
OCGA § 17-7-190