关于备份还原sqlserver2000的问题

我利用
sqlca.autocommit = true
ls_sql = "BACKUP DATABASE" + space(1) + ls_datebase_name + space(1) + "to disk='" + ls_bkfilename + "'"
EXECUTE IMMEDIATE :ls_sql;顺利备份成功

但是在用
ls_reg_path = "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\Currentversion\Uninstall\Microsoft SQL Server 2000"
RegistryGet(ls_reg_path, "InstallLocation", RegString!, ls_install_path)
ls_install_path = ls_install_path + "\Data\"

ls_bkfilename = trim(sle_2.text)

ls_datebase_name = "bookstore"
ls_date_logic_name = "bookstore_Data"
ls_log_logic_name = "bookstore_Log"
ls_date_reality_name = "bookstore.mdf"
ls_log_reality_name = "bookstore.ldf"

//还原数据库
SQLCA.AutoCommit = true
ls_sql = "RESTORE DATABASE" + space(1) + ls_datebase_name + space(1) + "FROM DISK = " + ls_bkfilename + space(1) + &
"WITH MOVE" + space(1) + "'" + ls_date_logic_name + "'" + space(1) + "TO" + space(1) + "'" + ls_install_path + ls_date_reality_name + "'," + &
MOVE" + space(1) + "'" + ls_log_logic_name + "'" + space(1) + "TO" + space(1) + "'" + ls_install_path + ls_log_reality_name + "'"

EXECUTE IMMEDIATE :ls_sql;

还原是老是提示还原失败，sqlca.code = -1 不知道是什么原因，请解释