JDBC模板中的Select语句

Question

After running program I receive error message:

Caused by: org.springframework.jdbc.UncategorizedSQLException: PreparedStatementCallback; uncategorized SQLException for SQL [SELECT * FROM products WHERE productname = ?]; SQL state [S0022]; error code [0]; Column 'categoryname' not found.; nested exception is java.sql.SQLException: Column 'categoryname' not found.

   @Repository
public class JdbcProductsDao implements ProductsDao{

    private final JdbcTemplate jdbcTemplate;

    @Autowired
    public JdbcProductsDao(JdbcTemplate jdbcTemplate) {
        this.jdbcTemplate = jdbcTemplate;
    }

    private static final RowMapper<Products> productsRowMapper = (rs, rowNum) ->{
        Products products = new Products();
        products.setProductid(rs.getLong("ProductID"));
        products.setProductname(rs.getString("ProductName"));
        products.setSupplierid(rs.getLong("SupplierID"));
        products.setCategoryid(new Categories(rs.getString("CategoryName")));
        products.setQuantityperunit(rs.getString("QuantityPerUnit"));
        products.setUnitprice(rs.getDouble("UnitPrice"));
        products.setUnitsinstock(rs.getLong("UnitsInStock"));
        products.setUnitsonorder(rs.getLong("UnitsOnOrder"));
        products.setReorderlevel(rs.getLong("ReorderLevel"));
        products.setDiscontinued(rs.getString("Discontinued"));
        return products;
    };


    public Products findByProductName(String productname) {
        String sql = "SELECT * FROM products WHERE ProductName = ?";
        return jdbcTemplate.queryForObject(sql, productsRowMapper, productname);
    }

    public List<Products> sortByProductName(){
        String sql = "SELECT * FROM products order by ProductName asc";
        return jdbcTemplate.query(sql, productsRowMapper);
        }

Table Categories

@Entity
public class Categories {
  @Id
  private Long categoryid;
  @Column(name = "CategoryName")
  private String categoryname;
  private String description;
  private String picture;

  @OneToMany(mappedBy="categoryid")
  private List<Products> products;

Table Products

   @Entity
public class Products {
  @Id
  private Long productid;
  @Column(name = "ProductName")
  private String productname;
  private Long supplierid;
  @ManyToOne
  private Categories categoryid;
  private String quantityperunit;
  private Double unitprice;
  private Long unitsinstock;
  private Long unitsonorder;
  private Long reorderlevel;
  private String discontinued;

Can You tell me what I'm doing wrong?

Answer 1

Problem is solved, I changed select statement to

public Products findByProductName(String productname) {
        String sql = "SELECT ProductID, ProductName, SupplierID, CategoryID, QuantityPerUnit, UnitPrice, UnitsInStock, UnitsOnOrder, ReorderLevel, Discontinued  FROM products WHERE ProductName = ?";
        return jdbcTemplate.queryForObject(sql, productsRowMapper, productname);
    }`