選擇一個額外的空行不存在

Question

可能重複：
Include a blank row in query results

我想一個空行添加到我的結果集在我的SQL查詢的最頂端。

我使用的查詢是這樣的：

SELECT 
    PROFILETITLE, DOCID 
FROM 
    PROFILES 
WHERE 
    COMPANYCODE = ? 
ORDER BY 
    PROFILETITLE 

Answer 1

嘗試使用union all

SELECT null as PROFILETITLE, null as DOCID 
UNION ALL 
SELECT PROFILETITLE, DOCID 
FROM PROFILES 
WHERE COMPANYCODE=? 
ORDER BY PROFILETITLE 

，但如果你不會添加標題，如果DOCID是int類型，你必須使用union all和cast如下

SELECT 'PROFILETITLE' as PROFILETITLE, 'DOCID' as DOCID 
UNION ALL 
SELECT PROFILETITLE, CAST (DOCID AS varchar(30)) 
FROM PROFILES 
WHERE COMPANYCODE=? 
ORDER BY PROFILETITLE 

Answer 2

試試這個：

SELECT '' AS PROFILETITLE, 0 AS DOCID 
UNION ALL 
SELECT PROFILETITLE, DOCID 
FROM PROFILES WHERE COMPANYCODE = ? 
ORDER BY PROFILETITLE 

注意，使用UNION時，和所有其他的操作集，列在類型相匹配，所以您必須將前兩個空值與PROFILETITLE和DOCID別名。爲了正常工作，您必須注意兩列的類型以及匹配。可能是您需要選擇NULL而不是''和0。

Answer 3

您可以使用SQL Union

SELECT PROFILETITLE, DOCID 
FROM PROFILES 
WHERE COMPANYCODE=? ORDER BY PROFILETITLE 
UNION ALL 
SELECT 0, '' 
FROM SYSIBM.SYSDUMMY1 

您可以用臨時表替換SYSIBM.SYSDUMMY1

Answer 4

工會都將做的工作

SELECT 
'' as PROFILETITLE, 
'' as DOCID 
UNION ALL 
SELECT PROFILETITLE, DOCID 
FROM PROFILES 
WHERE COMPANYCODE=? ORDER BY PROFILETITLE 

Answer 5

您可以添加一個「空行」，如果所有的列都varchar和空手段''這樣：

SELECT PROFILETITLE, DOCID 
FROM PROFILES 
WHERE ... 

UNION ALL 

SELECT '' AS PROFILETITLE, '' AS DOCID 

ORDER BY 
    CASE WHEN PROFILETITLE='' AND DOCID='' THEN 0 ELSE 1 END ASC 
, PROFILETITLE ASC