等式查询:
string sql="select id,classname,ordernum,bcid from tbcity where classname = :key<char[20]> order by ordernum"
string key="焦作市";
const char* ck= key.c_str();
o<<ck;
模糊查询:
string sql="select id,classname,ordernum,bcid from tbcity where classname like :key<char[20]> order by ordernum"
string key="%焦%";
const char* ck= key.c_str();
o<<ck;
以上两种均可查出结果