使用 SQL 根据固定字符长度将文本拆分为多行块

Question

我正在寻找 SQL 接受一串文本（最多 3 行，但通常为 1 行）并将其分成最多 3 行，每行最多 30 个字符。（背景是我试图将文本插入地址行字段，有时传入的值超过 30 个字符，需要拆分成更小的块并向下移动到另一行）。

我什至不知道从哪里开始。由于它是地址文本，因此存在相当大的差异，理想情况下，如果可能的话，它不应该在单词中间拆分。这将在 SQL Server 2012 中。有什么建议吗？

Answer 1

这应该使用递归 CTE 完成您想要的：

CREATE PROCEDURE REDISTRIBUTE_TEXT 
     @IN_LINE_1         VARCHAR(200)
    ,@IN_LINE_2         VARCHAR(200)
    ,@IN_LINE_3         VARCHAR(200)

    ,@MAX_LINE_LENGTH   INTEGER

    ,@OUT_LINE_1        VARCHAR(200) OUT
    ,@OUT_LINE_2        VARCHAR(200) OUT
    ,@OUT_LINE_3        VARCHAR(200) OUT
AS
BEGIN
    SET NOCOUNT ON;
        DECLARE @s VARCHAR(1000);

        SET @s = @IN_LINE_1 + ' ' + @IN_LINE_2 + ' ' + @IN_LINE_3;

        WITH CHAR_ARRAY AS (
            SELECT   v.number + 1                   Char_ID
                    ,SUBSTRING(a.b, v.number+1, 1)  Char_Value
            FROM    (SELECT @s b) a
            JOIN    master..spt_values v 
            ON      v.number < len(a.b)
            WHERE   v.type = 'P'
        )
        , WORD_ARRAY AS (
            SELECT   S.ID           AS Word_ID
                    ,S.Value        AS Word_Value
                    ,LEN(S.VALUE)   AS Word_Length
            FROM    dbo.String_Split_1(@s, ' ') S   -- This could be replaced with built-in STRING_SPLIT function in MSSQL 2016+
        )
        , WORD_EXT AS (
            SELECT  x.*
                    ,( 
                        SELECT   SUM(y.Word_Length) + COUNT(*)
                        FROM      WORD_ARRAY y
                        WHERE     y.Word_ID <= x.Word_ID
                    ) AS RunningLength
            FROM    WORD_ARRAY x
        )
        , CHAR_EXT AS (
            SELECT   C.*
                    ,W2.Word_ID     AS Next_Word_ID
                    ,W2.Word_Length AS Next_Word_Length
            FROM    (
                SELECT  C.*
                        ,W.*
                        ,ROW_NUMBER() OVER (PARTITION BY C.Char_ID ORDER BY RunningLength ASC) RN
                FROM    CHAR_ARRAY  C
                CROSS JOIN  WORD_EXT W
                WHERE   C.Char_ID <= W.RunningLength
            ) C
            LEFT JOIN   WORD_ARRAY W2
            ON      W2.Word_ID = C.Word_ID + 1
            WHERE RN = 1
        )
        , RECUR (CURR_CHAR_ID, START_WORD_ID, CURR_WORD_ID, LINE_NUM, LINE_TEXT, LINE_LENGTH) AS (
            SELECT   C.Char_ID
                    ,W.Word_ID
                    ,W.Word_ID
                    ,1
                    ,CAST(C.Char_Value AS VARCHAR)
                    ,LEN(C.Char_Value)
            FROM    CHAR_EXT C
            JOIN    WORD_EXT W
            ON      C.Word_ID = W.Word_ID
            WHERE   C.Char_ID = 1
            
            UNION ALL

            SELECT   CHAR_ID                                                                                    CURR_CHAR_ID
                    ,CASE WHEN WRAP_END_WORD = 1 THEN Next_Word_ID ELSE START_WORD_ID END                       START_WORD_ID
                    ,CASE WHEN WRAP_END_WORD = 1 THEN Next_Word_ID ELSE Word_ID END                             CURR_WORD_ID
                    ,CASE WHEN WRAP_END_WORD = 1 OR WRAP_MID_WORD = 1 THEN LINE_NUM + 1 ELSE LINE_NUM END       LINE_NUM
                    ,CAST(
                        CASE    WHEN WRAP_END_WORD = 1 OR WRAP_MID_WORD = 1 
                                THEN (CASE WHEN C.Char_Value = ' ' THEN '' ELSE C.Char_Value END )
                                ELSE LINE_TEXT + C.Char_Value 
                                END AS VARCHAR)                                                                 LINE_TEXT
                    ,CASE WHEN WRAP_END_WORD = 1 OR WRAP_MID_WORD = 1 THEN 1 ELSE LINE_LENGTH + 1 END           LINE_LENGTH
            FROM    (
                SELECT   R.*
                        ,C.*
                        ,CASE WHEN R.START_WORD_ID = C.WORD_ID AND LINE_LENGTH > @MAX_LINE_LENGTH 
                            THEN 1 ELSE 0 
                            END AS WRAP_MID_WORD
                        ,CASE WHEN C.Char_Value = ' ' AND (
                                    LEN(R.LINE_TEXT) + 1 + C.Next_Word_Length > @MAX_LINE_LENGTH
                                )
                            THEN 1 ELSE 0 
                            END AS WRAP_END_WORD
                FROM    RECUR R
                JOIN    CHAR_EXT C
                ON      C.Char_ID = R.CURR_CHAR_ID + 1
            ) C
        )

        SELECT  * 
        INTO    #LINES
        FROM (
            SELECT  * 
                    ,ROW_NUMBER() OVER (PARTITION BY LINE_NUM ORDER BY LEN(LINE_TEXT) DESC) RN
            FROM    RECUR R
        ) R
        WHERE RN = 1
        ;

        SELECT  @OUT_LINE_1 = LINE_TEXT FROM    #LINES WHERE    LINE_NUM = 1;
        SELECT  @OUT_LINE_2 = LINE_TEXT FROM    #LINES WHERE    LINE_NUM = 2;
        SELECT  @OUT_LINE_3 = LINE_TEXT FROM    #LINES WHERE    LINE_NUM = 3;

        DROP TABLE #LINES;
END
GO


CREATE Function [String_Split_1]( @string varchar(4000), @delimeter varchar(10))
Returns
@Result Table (ID int identity(1,1) not null, value varchar(100))
As
Begin
    declare @len int, @loc int = 1
    While @loc <= len(@string) 
    Begin
        Set @len = CHARINDEX(@delimeter, @string, @loc) - @loc
        If @Len < 0 Set @Len = len(@string)
        Insert Into @Result Values (SUBSTRING(@string,@loc,@len))
        Set @loc = @loc + @len + 1
    End
    Return
End

使用 SQL 根据固定字符长度将文本拆分为多行块

Split text into multiline chunks based on fixed character length using SQL

sql

tsql

sql-server

common-table-expression