c# - Convert.ToString 返回 `System.Byte[]` 而不是实际数据，因为 GROUP_CONCAT 返回 BLOB

Question

我有一种调用MySQL 过程的方法。以下是程序的一部分:

SELECT AR.alert_id AS AlertId,
        AR.rule_id AS RuleId,
        AR.name AS RuleName,
        AR.rule_type AS RuleType, 
        AR.description AS Description, 
        (SELECT group_concat(occured_event_id separator ', ') 
            FROM alert_rule_event
            WHERE alert_rule_id = AR.id) AS OccuredEventIds,
FROM alert_rule AR

C#代码:

alertRuleEntity.AlertId = Convert.ToInt32(dtAlertRuleEntityList.Rows[index]["AlertId"]);
alertRuleEntity.RuleId = Convert.ToInt32(dtAlertRuleEntityList.Rows[index]["RuleId"]);
alertRuleEntity.RuleName = Convert.ToString(dtAlertRuleEntityList.Rows[index]["RuleName"]);
alertRuleEntity.RuleType = Convert.ToString(dtAlertRuleEntityList.Rows[index]["RuleType"]);
alertRuleEntity.Description = Convert.ToString(dtAlertRuleEntityList.Rows[index]["Description"]);
alertRuleEntity.OccuredEventIds = Convert.ToString(dtAlertRuleEntityList.Rows[index]["OccuredEventIds"]);

返回值如下:

它能够正确读取所有列值。但是对于 OccuredEventIds 列，它给出的值是 System.Byte[] 而不是它的实际值。可能是什么问题？

Answer 1

在对我的程序进行以下更改后，它起作用了:

(SELECT group_concat(CONVERT(occured_event_id, CHAR(8)) separator ', ') 
FROM alert_rule_event
WHERE alert_rule_id = AR.id) AS OccuredEventIds