select ref_no as '档案号' , named_attorney2 as '案源', invention_title as '发明名称' ,client_id as '申请人',inventor_ctitle as '发明人' ,file_no as '申请号',file_date as '申请日',named_attorney as '代理人', actual_attorney as '撰稿人' from patent_primary where inventor_ctitle is null AND ref_no ='P10001EU*9'
我知道这个什么查询不到数据
select ref_no as '档案号' , named_attorney2 as '案源', invention_title as '发明名称' ,client_id as '申请人',inventor_ctitle as '发明人' ,file_no as '申请号',file_date as '申请日',named_attorney as '代理人', actual_attorney as '撰稿人' from patent_primary where named_attorney2 like '" + '%' + named_attorney2 + '%' + "' and named_attorney like '" + '%' + named_attorney + '%' + "' and actual_attorney like '" + '%' + actual_attorney + '%' + "' and invention_title like '" + '%' + invention_title + '%' + "' and client_id like '" + '%' + client_id + '%' + "' and file_no like '" + '%' + file_no + '%' + "' and ref_no like '" + '%' + ref_no + '%' + "' and inventor_ctitle like '" + '%' + inventor_ctitle + '%' + "'
因为数据中有NULL空值在？
