相比之下,说:
REPLICATE(@padchar, @len - LEN(@str)) + @str
相比之下,说:
REPLICATE(@padchar, @len - LEN(@str)) + @str
当前回答
在SQL Server 2005及以后的版本中,您可以创建一个CLR函数来完成此操作。
其他回答
下面是我的解决方案,它避免了截断字符串并使用普通的SQL。感谢@AlexCuse, @Kevin和@Sklivvz,他们的解决方案是这段代码的基础。
--[@charToPadStringWith] is the character you want to pad the string with.
declare @charToPadStringWith char(1) = 'X';
-- Generate a table of values to test with.
declare @stringValues table (RowId int IDENTITY(1,1) NOT NULL PRIMARY KEY, StringValue varchar(max) NULL);
insert into @stringValues (StringValue) values (null), (''), ('_'), ('A'), ('ABCDE'), ('1234567890');
-- Generate a table to store testing results in.
declare @testingResults table (RowId int IDENTITY(1,1) NOT NULL PRIMARY KEY, StringValue varchar(max) NULL, PaddedStringValue varchar(max) NULL);
-- Get the length of the longest string, then pad all strings based on that length.
declare @maxLengthOfPaddedString int = (select MAX(LEN(StringValue)) from @stringValues);
declare @longestStringValue varchar(max) = (select top(1) StringValue from @stringValues where LEN(StringValue) = @maxLengthOfPaddedString);
select [@longestStringValue]=@longestStringValue, [@maxLengthOfPaddedString]=@maxLengthOfPaddedString;
-- Loop through each of the test string values, apply padding to it, and store the results in [@testingResults].
while (1=1)
begin
declare
@stringValueRowId int,
@stringValue varchar(max);
-- Get the next row in the [@stringLengths] table.
select top(1) @stringValueRowId = RowId, @stringValue = StringValue
from @stringValues
where RowId > isnull(@stringValueRowId, 0)
order by RowId;
if (@@ROWCOUNT = 0)
break;
-- Here is where the padding magic happens.
declare @paddedStringValue varchar(max) = RIGHT(REPLICATE(@charToPadStringWith, @maxLengthOfPaddedString) + @stringValue, @maxLengthOfPaddedString);
-- Added to the list of results.
insert into @testingResults (StringValue, PaddedStringValue) values (@stringValue, @paddedStringValue);
end
-- Get all of the testing results.
select * from @testingResults;
我用这个。它允许您确定想要的结果长度,以及如果没有提供默认填充字符。当然,您可以为遇到的任何最大值定制输入和输出的长度。
/*===============================================================
Author : Joey Morgan
Create date : November 1, 2012
Description : Pads the string @MyStr with the character in
: @PadChar so all results have the same length
================================================================*/
CREATE FUNCTION [dbo].[svfn_AMS_PAD_STRING]
(
@MyStr VARCHAR(25),
@LENGTH INT,
@PadChar CHAR(1) = NULL
)
RETURNS VARCHAR(25)
AS
BEGIN
SET @PadChar = ISNULL(@PadChar, '0');
DECLARE @Result VARCHAR(25);
SELECT
@Result = RIGHT(SUBSTRING(REPLICATE('0', @LENGTH), 1,
(@LENGTH + 1) - LEN(RTRIM(@MyStr)))
+ RTRIM(@MyStr), @LENGTH)
RETURN @Result
END
你的里程可能会有所不同。: -) 乔伊摩根 一级程序设计/分析主任 WellPoint医疗补助事业单位
这个怎么样:
replace((space(3 - len(MyField))
3是要填充的零的个数
我喜欢vnRocks的解决方案,这里是一个udf的形式
create function PadLeft(
@String varchar(8000)
,@NumChars int
,@PadChar char(1) = ' ')
returns varchar(8000)
as
begin
return stuff(@String, 1, 0, replicate(@PadChar, @NumChars - len(@String)))
end
这是我通常如何填充一个varchar
WHILE Len(@String) < 8
BEGIN
SELECT @String = '0' + @String
END