详解Mybatis中的select方法

selectById方法

根据id，查询记录

public void updateRecycleAssayBusinessItemCharge(String Id) {
  AssayBusinessItemCharge assayBusinessItemCharge = assayBusinessItemChargeService.selectById(Id);
  assayBusinessItemCharge.setRecordStatus(RecordStatusEnum.VALID.getValue());
  assayBusinessItemChargeService.update(assayBusinessItemCharge);
}

selectByExample方法

根据实体字段，查询记录

public Account findByAccountName(String accountName) {
  AccountExample accountExample = new AccountExample();
  AccountExample.Criteria criteria = accountExample.createCriteria();
  criteria.andAccountNameEqualTo(accountName);
  List accountList = accountService.selectByExample(accountExample);
  if (accountList == null || accountList.size() != 1)
    return null;
  else
    return accountList.get(0);
}

查询所有list

传一个空的实体，不要给赋字段值

public Account findByAccountName(String accountName) {
  AccountExample accountExample = new AccountExample();
  AccountExample.Criteria criteria = accountExample.createCriteria();
  List accountList = accountService.selectByExample(accountExample);
  if (accountList == null || accountList.size() != 1)
    return null;
  else
    return accountList.get(0);
}

总结

以上所述是小编给大家介绍的Mybatis中的select方法，希望对大家有所帮助，如果大家有任何疑问请给我留言，小编会及时回复大家的。在此也非常感谢大家对考高分网网站的支持！