package modules.nftt; import com.jfinal.plugin.activerecord.Db; import common.model.Nftt; import java.util.List; public class NfttService { public String hello() { return "Hello Nftt"; } public boolean save(Nftt nftt) { return nftt.save(); } public Nftt findNfttById(String id) { return Nftt.dao.findById(id); } public Integer count() { String sql = "SELECT COUNT(1) FROM t_nftt"; return Db.queryInt(sql); } public List homeList() { String columns = "*"; String baseSql = "select " + columns + " from t_nftt order by buying_start_time desc limit 0, 10"; return Nftt.dao.find(baseSql); } public List nfttList(int pageNumber, int pageSize) { // limit 的第一个参数是偏移量,第二个参数是查询数量 // 正确的 limit 是 LIMIT offset, count // offset = (pageNumber - 1) * pageSize // count = pageSize int offset = (pageNumber - 1) * pageSize; String sql = "SELECT COUNT(1) FROM t_nftt"; String columns = "*"; String baseSql = "select " + columns + " from t_nftt order by buying_start_time desc limit ?, ?"; return Nftt.dao.find(baseSql, offset, pageSize); } }