insert into category(id,name,name_zh,parent_id) values(1,'qa','问答',0);
insert into category(id,name,name_zh,parent_id) values(10,'questions','问题',1);
insert into category(id,name,name_zh,parent_id) values(11,'answers','回答',1);
insert into category(id,name,name_zh,parent_id) values(2,'ns','供求',0);
insert into category(id,name,name_zh,parent_id) values(20,'need','技术需求',2);
insert into category(id,name,name_zh,parent_id) values(21,'supply','技术供应',2);