code: func PgShdescriptionByObjoidClassoid(db XODB, objoid pgtypes.Oid, classoid pgtypes.Oid) (*PgShdescription, error) {
  	var err error
  
  	// sql query
  	const sqlstr = `SELECT ` +
  		`tableoid, cmax, xmax, cmin, xmin, ctid, objoid, classoid, description ` +
  		`FROM pg_catalog.pg_shdescription ` +
  		`WHERE objoid = $1 AND classoid = $2`
  
  	// run query
  	XOLog(sqlstr, objoid, classoid)
  	ps := PgShdescription{}
  
  	err = db.QueryRow(sqlstr, objoid, classoid).Scan(&ps.Tableoid, &ps.Cmax, &ps.Xmax, &ps.Cmin, &ps.Xmin, &ps.Ctid, &ps.Objoid, &ps.Classoid, &ps.Description)
  	if err != nil {
  		return nil, err
  	}
  
  	return &ps, nil
  }
docs: // PgShdescriptionByObjoidClassoid retrieves a row from 'pg_catalog.pg_shdescription' as a PgShdescription.
  //
  // Generated from index 'pg_shdescription_o_c_index'.