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<Account> 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<Account> 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方法网站的支持！

来源：https://blog.csdn.net/nangeali/article/details/81278822