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Java apachedbutils和标量值_Java_Apache Commons Dbutils - Fatal编程技术网

Java apachedbutils和标量值

Java apachedbutils和标量值,java,apache-commons-dbutils,Java,Apache Commons Dbutils,我需要用DBUtils获取标量值,有人知道如何获取吗?目前我有: String sql = "SELECT count(*) FROM t1 WHERE cod = ?"; final QueryRunner run = new QueryRunner(new AppDataSource()); ScalarHandler scalar = new ScalarHandler(); long count = -1l; try{ Object

我需要用DBUtils获取标量值,有人知道如何获取吗?目前我有:

    String sql = "SELECT count(*) FROM t1 WHERE cod = ?";
    final QueryRunner run = new QueryRunner(new AppDataSource());
    ScalarHandler scalar = new ScalarHandler();
    long count = -1l;
    try{
        Object[] params =
        {
                code
        };
        count = ((Long) run.query(sql, scalar, params)).longValue();
    }
    catch(SQLException e){
        e.printStackTrace();
    }
    System.out.println(count);

但结果仍然是-1。当我用db util测试它时,我得到了正确的数字。

嗯,没有什么比将标准方案名称重命名为“public”(PostgreSQL)更好的了,也没有什么比不在SQL中使用它更好的了,这是正确的方法:

String sql = "SELECT count(*) FROM \"MySchema\".t1 WHERE cod = ?";

希望有人能帮上忙。

我希望下面的代码能帮助您,ScalarHandler只提取一个列值

public Object queryColumnVaue(String sql,String columnName) throws SQLException { 
     ScalarHandler<Object> kh = new ScalarHandler<Object>(columnName);
     return query(sql,kh);
 }
公共对象queryColumnVaue(字符串sql,字符串columnName)抛出SQLException{ ScalarHandler kh=新的ScalarHandler(columnName); 返回查询(sql,kh); }