sys_connect_by_path函式

用於多列轉行

語法格式
select … sys_connect_by_path(column_name,’connect_symbol’) from table
start with … connect by … prior

語法說明
column_name，欄位名
connect_symbol，兩個欄位之間的連線符號

start with，開始的地方，遍歷的起點
connect by，來尋找下一條記錄，直到迭代找不到相應記錄為止
指定遞迴(連線)條件，如果條件不滿足則遞迴結束
prior，參考值，寫在誰的前面誰就作為父級值（參照值）

SELECT
    c1 AS ASSAY_EQUIPMENT_ID,
    LTRIM (
        SYS_CONNECT_BY_PATH (c2, ','),
        ','
    ) ASSAY_ITEM_IDS,
    LTRIM (
        SYS_CONNECT_BY_PATH (c3, ','),
        ','
    ) ASSAY_ITEM_NAMES
FROM
    (
        SELECT
            c1,
            c2,
            c3,
            ROW_NUMBER () OVER (PARTITION BY
 
 c1 ORDER BY c2) rn
        FROM
            (
                SELECT
                    R1.ASSAY_EQUIPMENT_ID c1,
                    R1.ASSAY_ITEM_ID c2,
                    T1.ASSAY_ITEM_NAME c3
                FROM
                    CNF_ASSAY_ITEM_EQUI_RELA R1,
                    DIC_ASSAY_ITEM T1
                WHERE
 

                    R1.ASSAY_ITEM_ID = T1. ID
            )
    )
WHERE
    CONNECT_BY_ISLEAF = 1 CONNECT BY PRIOR rn + 1 = rn
AND PRIOR c1 = c1 START WITH rn = 1