trim_snapshots.py

import sqlite3, argparse

def remove_snapshots(fn):
    conn = sqlite3.connect(fn)
    c = conn.cursor()
    c.execute("SELECT id,contents from snapshot ORDER BY id DESC LIMIT 1;")
    last_snapshot,last_contents = c.fetchone()
    c.execute(f"UPDATE snapshot set parent=NULL;")
    c.execute(f"DELETE FROM snapshot WHERE id!={last_snapshot};")
    c.execute(f"DELETE FROM file_contents WHERE id!={last_contents};")
    c.execute(f"DELETE FROM file_section WHERE contents!={last_contents};")
    conn.commit()
    c.execute("VACUUM;")
    conn.close()

if __name__ == "__main__":
    parser = argparse.ArgumentParser(description='Remove old snapshots from BNDB')
    parser.add_argument('database', type=str, help='Database to trim')
    args = parser.parse_args()
    remove_snapshots(args.database)