fix division by 0 error

all.sql

@@ -2473,7 +2473,7 @@ CREATE TABLE `bi_app_backup_coverage` (
 		ia.PRIORITY,
 		sum(abi.bak_size),
 		sum(abi.total_size),
-		sum(abi.bak_size) / sum(abi.total_size)
+		IF(sum(abi.total_size)<>0, sum(abi.bak_size) / sum(abi.total_size), 0)
 	from t_asset_app_bak_info abi
 	left join itm_app ia on ia.ITM_APP_ID=abi.app_id
 	left join (select value,name from m_com_dict where dict_index='itm_resources_netcode') d on d.value=ia.ITM_NETGROUP_ID
@@ -2485,7 +2485,7 @@ CREATE TABLE `bi_app_backup_coverage` (
 		NET_ID,NET_NAME,ORGAN_ID,ORGAN_NAME,app_id,app_name,priority,
 		sum(bak_size),
 		sum(total_size),
-		sum(bak_size) / sum(total_size)
+		IF(sum(total_size)<>0, sum(bak_size) / sum(total_size), 0)
 	from bi_app_backup_coverage 
 	where dtype = 'MONTH'
 	GROUP BY substring(thedvalue,1,4),NET_ID,NET_NAME,ORGAN_ID,ORGAN_NAME,app_id,app_name,priority;