• 2022-06-11
    已知,存在 QueryRunner对象 runner , SQL语句: String sql = "select * from user where id=?"; 下面操作中,能实现查询指定记录的选项是()
  • User user=(User)runner.query(sql, new BeanHandler(User.class), new Object[]{id});

    举一反三

    内容

    • 0

      已知,存在 QueryRunner对象 runner , SQL语句:String sql = "select * from user";下面操作中,能实现查询所有记录的选项是( ) A: Object list=runner.query(sql, new BeanHandler<User>(User.class)); B: List list=runner.query(sql, new BeanHandler<User>(User.class)); C: List<User> list=runner.query(sql, new BeanHandler<User>(User.class)); D: List<User> list=runner.query(sql, new BeanListHandler<User>(User.class));Object num =runner.delete(1, sql);

    • 1

      【多选题】已知user表中存在一个字段id。 下面选项中,能够查询出id编号为u001和u002的用户的SQL语句是 A. select * from user where id = 'u001' and id = 'u002'; B. select * from user where id = 'u001' or id = 'u002'; C. select * from user where

    • 2

      已知用户表 user 有多列,其中字段 id 没有 NULL 值,字段username有NULL值,选项中,不能获得 user 表的总记录数量的 SQL 语句是 A: SELECT COUNT (*) FROM user ; B: SELECT COUNT ( id ) FROM user ; C: SELECT COUNT ( username ) FROM user ; D: SELECT COUNT ( id ) FROM user WHERE 1=1;

    • 3

      下面用于查询student表中id值在1,2,3范围内的记录的SQL语句是( )。 A: SELECT * FROM student WHERE id=1,2,3; B: SELECT * FROM student WHERE (id=1,id=2,id=3); C: SELECT * FROM student WHERE id in (1,2,3); D: SELECT * FROM student WHERE id in 1,2,3;

    • 4

      假定用户表user有多列,其中字段id中没有null值,字段username中存在null值。下面选项中,不能获得user表的总记录数的SQL语句是( ) A: select count(*) from user; B: select count(id) from user; C: select count(username) from user; D: select count(id) from user where1=1;