code: func PgCollationByOid(db XODB, oid pgtypes.Oid) (*PgCollation, error) {
  	var err error
  
  	// sql query
  	const sqlstr = `SELECT ` +
  		`tableoid, cmax, xmax, cmin, xmin, oid, ctid, collname, collnamespace, collowner, collencoding, collcollate, collctype ` +
  		`FROM pg_catalog.pg_collation ` +
  		`WHERE oid = $1`
  
  	// run query
  	XOLog(sqlstr, oid)
  	pc := PgCollation{}
  
  	err = db.QueryRow(sqlstr, oid).Scan(&pc.Tableoid, &pc.Cmax, &pc.Xmax, &pc.Cmin, &pc.Xmin, &pc.Oid, &pc.Ctid, &pc.Collname, &pc.Collnamespace, &pc.Collowner, &pc.Collencoding, &pc.Collcollate, &pc.Collctype)
  	if err != nil {
  		return nil, err
  	}
  
  	return &pc, nil
  }
docs: // PgCollationByOid retrieves a row from 'pg_catalog.pg_collation' as a PgCollation.
  //
  // Generated from index 'pg_collation_oid_index'.