字符串转换为表的几种方式
1.使用XQuery + OUTER APPLY，方便简洁，sql server 2005及以上使用。
SELECT T1.id
FROM ( SELECT p = CONVERT(XML, '' + REPLACE('1,2,3,4,5,6', ',',
' ') + ' ')
) T
OUTER APPLY ( SELECT id = TB.id.value('.', 'int')
FROM T.p.nodes('/id') TB ( id )
) T1;
2.使用字符串函数，需要对@str重新赋值
DECLARE @TB TABLE ( [id] VARCHAR(10) );
DECLARE @i INT ,
@str NVARCHAR(100);
SET @str = '1,2,3,4,5';
SET @i = CHARINDEX(',', @str);
WHILE ( @i >= 0 )
BEGIN
IF ( @i = 0 )
BEGIN
INSERT @TB
SELECT @str;
BREAK;
END;
INSERT @TB
SELECT LEFT(@str, @i - 1);
SET @str = RIGHT(@str, LEN(@str) - @i);
SET @i = CHARINDEX(',', @str);
END;
SELECT *
FROM @TB;3.使用identity，substring和 inner join 自连接，首尾要加分隔符，无需对@str重新赋值。
DECLARE @TB TABLE
(
row INT IDENTITY(1, 1) ,
location INT
);
DECLARE @split VARCHAR(1) ,
@str VARCHAR(100) ,
@i INT ,
@Len INT;
SET @split = ',';
SET @str = ',122,21,33,42,52,6,72,81,92,';
SET @Len = LEN(@str);
SET @i = 1;
WHILE ( @i <= @Len )
BEGIN
INSERT @TB
SELECT @i
WHERE SUBSTRING(@str, @i, 1) = @split;
SET @i = @i + 1;
END;
SELECT SUBSTRING(@str, T.location + 1, T1.location - T.location - 1)
FROM @TB T
INNER JOIN @TB T1 ON T.row + 1 = T1.row;