Pad a string with leading zeros so it's 3 characters long in SQL Server 2008

Question

I have a string that is up to 3 characters long when it\'s first created in SQL Server 2008 R2.

I would like to pad it with leading zeros, so if its original value w

Answer 1

I had similar problem with integer column as input when I needed fixed sized varchar (or string) output. For instance, 1 to '01', 12 to '12'. This code works:

SELECT RIGHT(CONCAT('00',field::text),2)

If the input is also a column of varchar, you can avoid the casting part.

Answer 2

If the field is already a string, this will work

 SELECT RIGHT('000'+ISNULL(field,''),3)

If you want nulls to show as '000'

It might be an integer -- then you would want

 SELECT RIGHT('000'+CAST(field AS VARCHAR(3)),3)

As required by the question this answer only works if the length <= 3, if you want something larger you need to change the string constant and the two integer constants to the width needed. eg '0000' and VARCHAR(4)),4

Answer 3

The safe method:

SELECT REPLACE(STR(n,3),' ','0')

This has the advantage of returning the string '***' for n < 0 or n > 999, which is a nice and obvious indicator of out-of-bounds input. The other methods listed here will fail silently by truncating the input to a 3-character substring.

Answer 4

I know this is an old ticket but I just thought I'd share this:

I found this code which provides a solution. Not sure if it works on all versions of MSSQL; I have MSSQL 2016.

declare @value as nvarchar(50) = 23
select REPLACE(STR(CAST(@value AS INT) + 1,4), SPACE(1), '0') as Leadingzero

This returns "0023".

The 4 in the STR function is the total length, including the value. For example, 4, 23 and 123 will all have 4 in STR and the correct amount of zeros will be added. You can increase or decrease it. No need to get the length on the 23.

Edit: I see it's the same as the post by @Anon.

Answer 5

For integers you can use implicit conversion from int to varchar:

SELECT RIGHT(1000 + field, 3)