如何使SQL查詢顯示兩列值到一列？

Question

我有一個如下所示的表結構。我想展示下名字的父（母地方是分類帳組）

Answer 1

DECLARE @t1 TABLE 
(
ParentGroup varchar(20), 
LedgerName varchar(20), 
TotalDebit float, 
credit float 
) 

INSERT INTO @t1 
SELECT * 
    FROM Table1 

INSERT INTO @t1 
SELECT Distinct ParentGroup, ParentGroup, NULL, NULL 
    FROM Table1 

Select LedgerName, TotalDebit, credit from @t1 
group by LedgerName, TotalDebit, credit 
ORDER BY (CASE WHEN TotalDebit IS NULL THEN 0 ELSE TotalDebit END)