Question

我想要一个TSQL表值函数，它可以执行嵌套解析并将结果返回到两列表中。

示例：

从udf_nested_split中选择*（'a - ＆gt; 1，b - ＆gt; 16，x - ＆gt; 99'）

会产生：

Tag|Value  
a|1  
b|16  
x|99

Answer 1

这是一个强力函数，但它有效...需要两个参数（一个用于主分隔符，一个用于辅助分隔符）：

IF EXISTS ( SELECT * from dbo.sysobjects WHERE id = object_id(N'[dbo].[doubleSplit]') 
            AND OBJECTPROPERTY(id, N'IsTableFunction') = 1 )
    DROP FUNCTION [dbo].[doubleSplit]
GO

CREATE FUNCTION dbo.doubleSplit ( 
        @sourceString varchar(MAX),
        @primaryDelimiter varchar(100),
        @secondaryDelimiter varchar(100) )
RETURNS @tblArray TABLE 
   (
    ElementID smallint IDENTITY(1,1),
    Element varchar(MAX),
    Value varchar(MAX)
   )
AS
BEGIN

    DECLARE @primaryIndex smallint
    DECLARE @secondaryIndex smallint
    DECLARE @primaryStart smallint
    DECLARE @secondaryStart smallint
    DECLARE @primaryDelimiterSize smallint
    DECLARE @seondaryDelimiterSize smallint
    DECLARE @primaryElement varchar(MAX);
    DECLARE @seondaryElement varchar(MAX);

    SET @primaryDelimiterSize = LEN(@primaryDelimiter)
    SET @seondaryDelimiterSize = LEN(@secondaryDelimiter)
    --loop through source string and add elements to destination table array
    WHILE LEN(@sourceString) > 0
    BEGIN
        SET @primaryIndex = CHARINDEX(@primaryDelimiter, @sourceString)
        IF @primaryIndex = 0
        BEGIN
            SET @secondaryIndex = CHARINDEX(@secondaryDelimiter, @sourceString)
            IF @secondaryIndex = 0
            BEGIN
                INSERT INTO @tblArray (Element, Value) VALUES(@sourceString, '')
            END
            ELSE
            BEGIN
                SET @secondaryStart = @secondaryIndex + @seondaryDelimiterSize;
                INSERT INTO @tblArray (Element, Value) 
                VALUES(SUBSTRING(@sourceString, 1, @secondaryIndex - 1), 
                       SUBSTRING(@sourceString, @secondaryIndex + @seondaryDelimiterSize, LEN(@sourceString) - @secondaryStart + 1))
            END
            BREAK
        END
        ELSE
        BEGIN
            SELECT @primaryElement = SUBSTRING(@sourceString, 1, @primaryIndex - 1);
            SET @secondaryIndex = CHARINDEX(@secondaryDelimiter, @primaryElement)
            SET @secondaryStart = @secondaryIndex + @seondaryDelimiterSize;
            INSERT INTO @tblArray (Element, Value) 
            VALUES(SUBSTRING(@primaryElement, 1, @secondaryIndex - 1), 
                   SUBSTRING(@primaryElement, @secondaryIndex + @seondaryDelimiterSize, LEN(@primaryElement) - @secondaryStart + 1))
            SET @primaryStart = @primaryIndex + @primaryDelimiterSize
            SET @sourceString = SUBSTRING(@sourceString, @primaryStart , LEN(@sourceString) - @primaryStart + 1)
        END
    END

    RETURN
END
GO

然后您可以这样调用它并获得预期结果：

SELECT * FROM dbo.doubleSplit('a-->1,b-->16,x-->99', ',', '-->')

返回：

ElementID   Element Value
1           a       1
2           b       16
3           x       99

而且：

SELECT * FROM dbo.doubleSplit('a-->1', ',', '-->')

返回：

ElementID  Element  Value
1          a        1

等等。

TSQL：嵌套分割/解析字符串到表（多个连接标签：一个字符串中的值）

1 个答案: