Oracle Error Workaround
在实际项目中使用ORACLE时出现的一些问题,通过变通的方案将问题避免了,特撰此文,以备忘用!1.ORA-01403:NO DATA FOUND-未找到
在实际项目中使用Oracle时出现的一些问题,通过变通的方案将问题避免了,特撰此文,,以备忘用!
1.ORA-01403:NO DATA FOUND-未找到数据
a.加一个exception异常处理
EXCEPTION WHEN NO_DATA_FOUND THEN ...
b.先用count计算一下是否大于0,即是否有值,这样就算没有值也会返回0,而不是NULL
SELECT COUNT(*) INTO FIELD FROM TABLE WHERE ...
2.ORA-01704:STRING LITERAL TOO LONG-文字字符串过长
直接用类似INSERT INTO TABLE (ID,CONTEXT) VALUES('1','...')语句向ORACLE插入长字节的字段CONTEXT时会出现此错误信息
a.在程序中可以利用参数来实现
C#代码
1 OracleConnection ocon = new OracleConnection();
2 OracleCommand ocom = new OracleCommand(sql, ocon);
3 ocom.Connection.Open();
4 ocom.Parameters.Add(":Value", OracleType.Blob);
5 ocom.Parameters[":Value"].Value = longvalue;
6 ocom.ExecuteNonQuery();
b.利用存储过程来实现相对比较简单,只要将参数传入即可
DECLARE
v_context CLOB :='long context';
BEGIN
INSERT INTO TABLE (ID,CONTEXT) VALUES ('1',:v_context);
END;

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