如何使用打印语句打印 VARCHAR(MAX)？

Question

我有一个代码是：

DECLARE @Script VARCHAR(MAX)

SELECT @Script = definition FROM manged.sys.all_sql_modules sq
where sq.object_id = (SELECT object_id from managed.sys.objects 
Where type = 'P' and Name = 'usp_gen_data')

Declare @Pos int

SELECT  @pos=CHARINDEX(CHAR(13)+CHAR(10),@script,7500)

PRINT SUBSTRING(@Script,1,@Pos)

PRINT SUBSTRING(@script,@pos,8000)

脚本的长度约为 10,000 个字符，由于我使用的 print 语句最多只能容纳 8000 个字符。所以我使用了两个 print 语句。

问题是当我有一个 18000 个字符的脚本时，我曾经使用 3 个打印语句。

那么有没有办法可以根据脚本的长度设置打印语句的数量？

Answer 1

我知道这是一个老问题，但这里没有提到我所做的。

对我来说，以下工作。

DECLARE @info NVARCHAR(MAX)

--SET @info to something big

PRINT CAST(@info AS NTEXT)

Answer 2

以下解决方法不使用PRINT 语句。它与 SQL Server Management Studio 结合使用效果很好。

SELECT CAST('<root><![CDATA[' + @MyLongString + ']]></root>' AS XML)

您可以单击返回的 XML 在内置的 XML 查看器中展开它。

对显示的大小有相当大的客户端限制。如果需要，请转到Tools/Options/Query Results/SQL Server/Results to Grid/XML data 进行调整。

Answer 3

这是应该如何完成的：

DECLARE @String NVARCHAR(MAX);
DECLARE @CurrentEnd BIGINT; /* track the length of the next substring */
DECLARE @offset tinyint; /*tracks the amount of offset needed */
set @string = replace(  replace(@string, char(13) + char(10), char(10))   , char(13), char(10))

WHILE LEN(@String) > 1
BEGIN
    IF CHARINDEX(CHAR(10), @String) between 1 AND 4000
    BEGIN
           SET @CurrentEnd =  CHARINDEX(char(10), @String) -1
           set @offset = 2
    END
    ELSE
    BEGIN
           SET @CurrentEnd = 4000
            set @offset = 1
    END   
    PRINT SUBSTRING(@String, 1, @CurrentEnd) 
    set @string = SUBSTRING(@String, @CurrentEnd+@offset, LEN(@String))   
END /*End While loop*/

取自http://ask.sqlservercentral.com/questions/3102/any-way-around-the-print-limit-of-nvarcharmax-in-s.html

Answer 4

我刚刚从Ben's 很棒的answer 创建了一个 SP：

/*
---------------------------------------------------------------------------------
PURPOSE   : Print a string without the limitation of 4000 or 8000 characters.
https://*.com/questions/7850477/how-to-print-varcharmax-using-print-statement
USAGE     : 
DECLARE @Result NVARCHAR(MAX)
SET @Result = 'TEST'
EXEC [dbo].[Print_Unlimited] @Result
---------------------------------------------------------------------------------
*/
ALTER PROCEDURE [dbo].[Print_Unlimited]
    @String NVARCHAR(MAX)
AS

BEGIN

    BEGIN TRY
    ---------------------------------------------------------------------------------

    DECLARE @CurrentEnd BIGINT; /* track the length of the next substring */
    DECLARE @Offset TINYINT; /* tracks the amount of offset needed */
    SET @String = replace(replace(@String, CHAR(13) + CHAR(10), CHAR(10)), CHAR(13), CHAR(10))

    WHILE LEN(@String) > 1
    BEGIN
        IF CHARINDEX(CHAR(10), @String) BETWEEN 1 AND 4000
        BEGIN
            SET @CurrentEnd =  CHARINDEX(CHAR(10), @String) -1
            SET @Offset = 2
        END
        ELSE
        BEGIN
            SET @CurrentEnd = 4000
            SET @Offset = 1
        END   
        PRINT SUBSTRING(@String, 1, @CurrentEnd) 
        SET @String = SUBSTRING(@String, @CurrentEnd + @Offset, LEN(@String))   
    END /*End While loop*/

    ---------------------------------------------------------------------------------
    END TRY
    BEGIN CATCH
        DECLARE @ErrorMessage VARCHAR(4000)
        SELECT @ErrorMessage = ERROR_MESSAGE()    
        RAISERROR(@ErrorMessage,16,1)
    END CATCH
END

Answer 5

遇到了这个问题，想要一些更简单的...试试以下：

SELECT [processing-instruction(x)]=@Script FOR XML PATH(''),TYPE

Answer 6

或者简单地说：

PRINT SUBSTRING(@SQL_InsertQuery, 1, 8000)
PRINT SUBSTRING(@SQL_InsertQuery, 8001, 16000)

Answer 7

我的 PrintMax 版本，用于防止输出错误的换行符：

    CREATE PROCEDURE [dbo].[PrintMax](@iInput NVARCHAR(MAX))
    AS
    BEGIN
      Declare @i int;
      Declare @NEWLINE char(1) = CHAR(13) + CHAR(10);
      While LEN(@iInput)>0 BEGIN
        Set @i = CHARINDEX(@NEWLINE, @iInput)
        if @i>8000 OR @i=0 Set @i=8000
        Print SUBSTRING(@iInput, 0, @i)
        Set @iInput = SUBSTRING(@iInput, @i+1, LEN(@iInput))
      END
    END

Answer 8

您可以根据脚本长度除以 8000 的计数执行 WHILE 循环。

EG：

DECLARE @Counter INT
SET @Counter = 0
DECLARE @TotalPrints INT
SET @TotalPrints = (LEN(@script) / 8000) + 1
WHILE @Counter < @TotalPrints 
BEGIN
    -- Do your printing...
    SET @Counter = @Counter + 1
END

Answer 9

你可以用这个

declare @i int = 1
while Exists(Select(Substring(@Script,@i,4000))) and (@i < LEN(@Script))
begin
     print Substring(@Script,@i,4000)
     set @i = @i+4000
end

Answer 10

考虑到包装，此过程正确打印出VARCHAR(MAX) 参数：

CREATE PROCEDURE [dbo].[Print]
    @sql varchar(max)
AS
BEGIN
    declare
        @n int,
        @i int = 0,
        @s int = 0, -- substring start posotion
        @l int;     -- substring length

    set @n = ceiling(len(@sql) / 8000.0);

    while @i < @n
    begin
        set @l = 8000 - charindex(char(13), reverse(substring(@sql, @s, 8000)));
        print substring(@sql, @s, @l);
        set @i = @i + 1;
        set @s = @s + @l + 2; -- accumulation + CR/LF
    end

    return 0
END

Answer 11

有一个很棒的函数叫做PrintMax written by Bennett Dill。

这里是稍微修改的版本，它使用临时存储过程来避免“模式污染”（来自https://github.com/Toolien/sp_GenMerge/blob/master/sp_GenMerge.sql 的想法）

EXEC (N'IF EXISTS (SELECT * FROM tempdb.sys.objects 
                   WHERE object_id = OBJECT_ID(N''tempdb..#PrintMax'') 
                   AND type in (N''P'', N''PC''))
    DROP PROCEDURE #PrintMax;');
EXEC (N'CREATE PROCEDURE #PrintMax(@iInput NVARCHAR(MAX))
AS
BEGIN
    IF @iInput IS NULL
    RETURN;

    DECLARE @ReversedData NVARCHAR(MAX)
          , @LineBreakIndex INT
          , @SearchLength INT;

    SET @SearchLength = 4000;

    WHILE LEN(@iInput) > @SearchLength
    BEGIN
    SET @ReversedData = LEFT(@iInput COLLATE DATABASE_DEFAULT, @SearchLength);
    SET @ReversedData = REVERSE(@ReversedData COLLATE DATABASE_DEFAULT);
    SET @LineBreakIndex = CHARINDEX(CHAR(10) + CHAR(13),
                          @ReversedData COLLATE DATABASE_DEFAULT);
    PRINT LEFT(@iInput, @SearchLength - @LineBreakIndex + 1);
    SET @iInput = RIGHT(@iInput, LEN(@iInput) - @SearchLength 
                        + @LineBreakIndex - 1);
    END;

    IF LEN(@iInput) > 0
    PRINT @iInput;
END;');

DBFiddle Demo

编辑：

使用 CREATE OR ALTER 我们可以避免两次 EXEC 调用：

EXEC (N'CREATE OR ALTER PROCEDURE #PrintMax(@iInput NVARCHAR(MAX))
AS
BEGIN
    IF @iInput IS NULL
    RETURN;

    DECLARE @ReversedData NVARCHAR(MAX)
          , @LineBreakIndex INT
          , @SearchLength INT;

    SET @SearchLength = 4000;

    WHILE LEN(@iInput) > @SearchLength
    BEGIN
    SET @ReversedData = LEFT(@iInput COLLATE DATABASE_DEFAULT, @SearchLength);
    SET @ReversedData = REVERSE(@ReversedData COLLATE DATABASE_DEFAULT);
    SET @LineBreakIndex = CHARINDEX(CHAR(10) + CHAR(13), @ReversedData COLLATE DATABASE_DEFAULT);
    PRINT LEFT(@iInput, @SearchLength - @LineBreakIndex + 1);
    SET @iInput = RIGHT(@iInput, LEN(@iInput) - @SearchLength + @LineBreakIndex - 1);
    END;

    IF LEN(@iInput) > 0
    PRINT @iInput;
END;');

db<>fiddle Demo

Answer 12

我想使用 print 语句来调试一些动态 sql，因为我想你们中的大多数人出于类似的原因使用 print。

我尝试了一些列出的解决方案，发现 Kelsey 的解决方案适用于较小的 tweeks（@sql 是我的 @script）n.b。 LENGTH 不是一个有效的函数：

--http://*.com/questions/7850477/how-to-print-varcharmax-using-print-statement
--Kelsey
DECLARE @Counter INT
SET @Counter = 0
DECLARE @TotalPrints INT
SET @TotalPrints = (LEN(@sql) / 4000) + 1
WHILE @Counter < @TotalPrints 
BEGIN
    PRINT SUBSTRING(@sql, @Counter * 4000, 4000)
    SET @Counter = @Counter + 1
END
PRINT LEN(@sql)

此代码确实按照注释在输出中添加了一个新行，但是对于调试这对我来说不是问题。

Ben B 的解决方案是完美的，也是最优雅的，虽然为了调试需要很多代码行，所以我选择使用我对 Kelsey 的轻微修改。是否值得在 msdb 中为 Ben B 的代码创建一个类似存储过程的系统，这样可以在一行中重复使用和调用？

不幸的是，Alfoks 的代码不起作用，因为那样会更容易。

Answer 13

使用换行符和空格作为一个很好的断点：

declare @sqlAll as nvarchar(max)
set @sqlAll = '-- Insert all your sql here'

print '@sqlAll - truncated over 4000'
print @sqlAll
print '   '
print '   '
print '   '

print '@sqlAll - split into chunks'
declare @i int = 1, @nextspace int = 0, @newline nchar(2)
set @newline = nchar(13) + nchar(10)


while Exists(Select(Substring(@sqlAll,@i,3000))) and (@i < LEN(@sqlAll))
begin
    while Substring(@sqlAll,@i+3000+@nextspace,1) <> ' ' and Substring(@sqlAll,@i+3000+@nextspace,1) <> @newline
    BEGIN
        set @nextspace = @nextspace + 1
    end
    print Substring(@sqlAll,@i,3000+@nextspace)
    set @i = @i+3000+@nextspace
    set @nextspace = 0
end
print '   '
print '   '
print '   '

Answer 14

创建过程 dbo.PrintMax @text nvarchar(max) 作为 开始 声明@i int、@newline nchar(2)、@print varchar(max)； 设置@newline = nchar(13) + nchar(10); 选择 @i = charindex(@newline, @text); 而 (@i > 0) 开始 选择@print = substring(@text,0,@i); 而 (len(@print) > 8000) 开始 打印子字符串（@print,0,8000）； 选择@print = substring(@print,8000,len(@print)); 结尾 打印@print； 选择@text = substring(@text,@i+2,len(@text)); 选择 @i = charindex(@newline, @text); 结尾 打印@文本； 结尾

Answer 15

这是另一个版本。这个从主字符串中提取要打印的每个子字符串，而不是在每个循环中将主字符串减少 4000（这可能会在后台创建很多非常长的字符串 - 不确定）。

CREATE PROCEDURE [Internal].[LongPrint]
    @msg nvarchar(max)
AS
BEGIN

    -- SET NOCOUNT ON reduces network overhead
    SET NOCOUNT ON;

    DECLARE @MsgLen int;
    DECLARE @CurrLineStartIdx int = 1;
    DECLARE @CurrLineEndIdx int;
    DECLARE @CurrLineLen int;   
    DECLARE @SkipCount int;

    -- Normalise line end characters.
    SET @msg = REPLACE(@msg, char(13) + char(10), char(10));
    SET @msg = REPLACE(@msg, char(13), char(10));

    -- Store length of the normalised string.
    SET @MsgLen = LEN(@msg);        

    -- Special case: Empty string.
    IF @MsgLen = 0
    BEGIN
        PRINT '';
        RETURN;
    END

    -- Find the end of next substring to print.
    SET @CurrLineEndIdx = CHARINDEX(CHAR(10), @msg);
    IF @CurrLineEndIdx BETWEEN 1 AND 4000
    BEGIN
        SET @CurrLineEndIdx = @CurrLineEndIdx - 1
        SET @SkipCount = 2;
    END
    ELSE
    BEGIN
        SET @CurrLineEndIdx = 4000;
        SET @SkipCount = 1;
    END     

    -- Loop: Print current substring, identify next substring (a do-while pattern is preferable but TSQL doesn't have one).
    WHILE @CurrLineStartIdx < @MsgLen
    BEGIN
        -- Print substring.
        PRINT SUBSTRING(@msg, @CurrLineStartIdx, (@CurrLineEndIdx - @CurrLineStartIdx)+1);

        -- Move to start of next substring.
        SET @CurrLineStartIdx = @CurrLineEndIdx + @SkipCount;

        -- Find the end of next substring to print.
        SET @CurrLineEndIdx = CHARINDEX(CHAR(10), @msg, @CurrLineStartIdx);
        SET @CurrLineLen = @CurrLineEndIdx - @CurrLineStartIdx;

        -- Find bounds of next substring to print.              
        IF @CurrLineLen BETWEEN 1 AND 4000
        BEGIN
            SET @CurrLineEndIdx = @CurrLineEndIdx - 1
            SET @SkipCount = 2;
        END
        ELSE
        BEGIN
            SET @CurrLineEndIdx = @CurrLineStartIdx + 4000;
            SET @SkipCount = 1;
        END
    END
END

Answer 16

这应该可以正常工作，这只是对以前答案的改进。

DECLARE @Counter INT
DECLARE @Counter1 INT
SET @Counter = 0
SET @Counter1 = 0
DECLARE @TotalPrints INT
SET @TotalPrints = (LEN(@QUERY) / 4000) + 1
print @TotalPrints 
WHILE @Counter < @TotalPrints 
BEGIN
-- Do your printing...
print(substring(@query,@COUNTER1,@COUNTER1+4000))

set @COUNTER1 = @Counter1+4000
SET @Counter = @Counter + 1
END

Answer 17

如果源代码不存在LF替换为CRLF的问题，则按照简单的代码输出无需调试。

--http://*.com/questions/7850477/how-to-print-varcharmax-using-print-statement
--Bill Bai
SET @SQL=replace(@SQL,char(10),char(13)+char(10))
SET @SQL=replace(@SQL,char(13)+char(13)+char(10),char(13)+char(10) )
DECLARE @Position int 
WHILE Len(@SQL)>0 
BEGIN
SET @Position=charindex(char(10),@SQL)
PRINT left(@SQL,@Position-2)
SET @SQL=substring(@SQL,@Position+1,len(@SQL))
end;