写了一个复杂的sql语句

$sp_sql = "select sp_ProductNo, sp_ProductName,sp_Standard,sp_Unit,sum(sp_Amount) as amount from   rd_store_product  where sp_Id in (select wv_Id from  

rd_warehouse_voucher where wv_StoreHouse = \"$houseName\") group by sp_ProductNo "; 

$gp_sql = "select gp_ProductNo, gp_ProductName,gp_Standard,gp_Unit,sum(gp_Amount) as amount from   rd_get_product  where gp_Id in (select ob_Id from  

rd_outbound where ob_StoreHouse = \"$houseName\") group by gp_ProductNo "; 

echo ($sp_sql);

echo "<br>";

echo "<br>";

echo ($gp_sql);

//exit();

$houseSql = "select a.sp_ProductNo,a.sp_ProductName, a.sp_Standard,a.sp_unit,a.amount - ifnull(b.amount,0) as last_amount from (".$sp_sql.") a left join (".$gp_sql.") b on a.sp_ProductNo =b.gp_ProductNo limit $offset,$limit";

echo "<br>";echo "<br>";

echo "$houseSql";

exit();