左外连接在oracle中未按预期工作

Question

我正在研究oracle数据库，我想从2个表中获取数据。所以我正在使用join。我的表格如下，

CUSTOMER_DTLS_TBL

CUST_ID     CUST_CODE

68          A2157021570

CUSTOMER_MAPPING_TBL

ID      AMOUNT      CUST_ID     CODE            PID 
1       200         68          A2157021570     383
2       800         68          A2157021570     392


// NO RECORD FOUND

SELECT CDT.CUST_ID,CDT.CUST_CODE,CMT.AMOUNT,CMT.PID
FROM CUSTOMER_DTLS_TBL CDT, CUSTOMER_MAPPING_TBL CMT
WHERE CDT.CUST_ID = CMT.CUST_ID(+)
AND CMT.PID = 383;


// 1 RECORD FOUND

SELECT CDT.CUST_ID,CDT.CUST_CODE,CMT.AMOUNT,CMT.PID
FROM CUSTOMER_DTLS_TBL CDT, CUSTOMER_MAPPING_TBL CMT
WHERE CDT.CUST_ID = CMT.CUST_ID(+)
AND CMT.PID = 392;

我运行第一个查询时的预期输出是：

68      A2157021570     200     383