1=1 ${if(len(item_id) == 0 ,"" ,"and item_code = '"+ item_id +"' " )}
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1=1 ${if( item_id== "未完成" ,"" ,"and item_code = '"+ item_id +"' " )}
1=1 ${if( item_id== "未完成" ,"" ,"and item_code = '固定值' " )}