在mssql中查询行数据作为列？

Question

我有以下表格

1. Ledger
LedgerId       LedgerName
  1            Cash acoount
  2            My Account

2. Transaction 
TransactionId      EntryDate
     1             26/5/2014

3. DebitCredit
DebitCreditId      TransactionId   LedgerId    IsDebit    Amount
      1                 1             1           0       50.00
      2                 1             2           1       50.00

我的输出应该是

Date         Debit Ledger Name         Credit Ledger Name      Amount
26/5/2014     My Account                   Cash Account          50

如果IsDebit为1，则相应的分类帐名称将显示为借方分类帐名称，否则将显示为贷方分类帐名称

请提供此

的查询

帮帮我 感谢

Answer 1

这可以使用JOINs：

来实现

SELECT  Date = t.EntryDate,
        DebitLedgerName = dl.LedgerName,
        CreditLedgerName = cl.LedgerName,
        d.Amount
FROM    [Transaction] AS t
        INNER JOIN DebitCredit AS d
            ON d.TransactionID = t.TransactionID
            AND d.IsDebit = 1
        INNER JOIN Ledger AS dl
            ON dl.LedgerID = d.LedgerID
        INNER JOIN DebitCredit AS c
            ON c.TransactionID = t.TransactionID
            AND c.IsDebit = 0
        INNER JOIN Ledger AS cl
            ON cl.LedgerID = c.LedgerID;

<强> Example on SQL Fiddle