Question

Java中对mssql数据库查询，怎么只能得到第一条记录？

public class ProductDAOImpl implements ProductDAO {

private Connection conn = null;
public ProductDAOImpl(Connection conn) {
this.conn = conn;
}

public ArrayList getAllProduct(String productc) throws Exception {
boolean flag = false;
java.sql.PreparedStatement pstmt = null;
ArrayList arrayList = new ArrayList();
try {
String sql = "SELECT * FROM product WHERE productcaid=?" ;
pstmt = this.conn.prepareStatement(sql) ;
pstmt.setString(1, productc) ;

ResultSet rs = pstmt.executeQuery() ;
if(rs.next()){

Product product=new Product();
product.setProductid(rs.getString(1));
product.setProductca(rs.getString(2));
product.setProductname(rs.getString(3));
product.setProductcontent(rs.getString(4));
product.setProductdescription(rs.getString(5));
product.setPrice(rs.getInt(6));
product.setMemberprice(rs.getInt(7));
product.setIsonsale(rs.getString(8));
product.setPicture(rs.getString(9));
System.out.println("product.getProductid()"+product.getProductid());
arrayList.add(product);
}
} catch (Exception e) {
throw e;
} finally {
try {
pstmt.close();
} catch (Exception e) {
throw e;
}
}
System.out.println("arrayList.size()="+arrayList.size());//这里测试的size结果为1，本来数据库中符合条件的有很多条记录
return arrayList;
}
}
我已经试过换成while了，也不行

Answer 1

if(rs.next()){

Product product=new Product();
product.setProductid(rs.getString(1));

在你的代码中if改为while