dalian-nft-api/src/main/java/modules/nftt/NfttService.java

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<Nftt> nfttListByUser() {
        String sql = "SELECT COUNT(1) FROM t_nftt";
        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<Nftt> 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);
    }
}