旧式 JOIN 语法在 T-SQL 中意味着什么？

Question

我需要编辑旧式 T-SQL 代码。

• 什么是=*意思？

• 这是什么*=意思？

我认为它们是 JOIN，但我不知道它们各自的 JOIN 类型是什么。

Answer 1

我找到答案了！

-- Example 1: Deprecated syntax for an inner join
SELECT [T2].[c3], [T1].[c3] 
FROM [dbo].[Table2] T2, [dbo].[Table1] T1 
WHERE [T1].[ID] = [T2].[ID]

-- Example 2: Current syntax for an inner join
SELECT [T2].[c3], [T1].[c3] 
FROM [dbo].[Table2] AS T2
INNER JOIN [dbo].[Table1] as T1
ON [T2].[ID] = [T1].[ID]

-- Example 3: Deprecated syntax for a left outer join
SELECT [T2].[c3], [T1].[c3] 
FROM [dbo].[Table2] T2, [dbo].[Table1] T1 
WHERE [T1].[ID] *= [T2].[ID]

-- Example 4: Fixed syntax for a left outer join
SELECT [T2].[c3], [T1].[c3] 
FROM [dbo].[Table2] AS T2
LEFT OUTER JOIN [dbo].[Table1] as T1
ON [T2].[ID] = [T2].[ID]

-- Example 5: Deprecated syntax for a right outer join
SELECT [T2].[c3], [T1].[c3] 
FROM [dbo].[Table2] T2, [dbo].[Table1] T1 
WHERE [T1].[ID] =* [T2].[ID]

-- Example 6: Fixed syntax for a right outer join
SELECT [T2].[c3], [T1].[c3] 
FROM [dbo].[Table2] AS T2
RIGHT OUTER JOIN [dbo].[Table1] as T1
ON [T2].[ID] = [T2].[ID]

https://msdn.microsoft.com/en-us/library/dd172122(v=vs.100).aspx