Left fill variable with zeros in FORMATMESSAGE

Question

Using SQL Server's FORMATMESSAGE command, I am printing status messages:

PRINT FORMATMESSAGE('Run time #%2d: From %s to %s', @i, CONVERT(VARCHAR(10), @from_date, 101), CONVERT(VARCHAR(10), @to_date, 101))

This gives me output like:

Run time # 8: From 03/21/2019 to 04/21/2019
Run time # 9: From 04/21/2019 to 05/21/2019
Run time #10: From 05/21/2019 to 06/21/2019
Run time #11: From 06/21/2019 to 07/21/2019

But how do I zero fill if the @i variable is less than 10. It gives me the two positions, but I can't figure out the character to left fill with zeros.

Answer 1

Try %0{# of digits}i (%02i) like so:

Declare @i int = 2

PRINT FORMATMESSAGE('La La La: %02i', @i)

-- OUTPUT: 'La La La: 02'

Your string:

PRINT FORMATMESSAGE('Run time #%02i: From %s to %s', @i, CONVERT(VARCHAR(10), @from_date, 101), CONVERT(VARCHAR(10), @to_date, 101))

Answer 2

UPDATE: it looks like FormatMessage supports more formatting options and you can easily specify as many leading 0's as you like:

PRINT FORMATMESSAGE('Run time #%02d: From %s to %s', @i, CONVERT(VARCHAR(10), @from_date, 101), CONVERT(VARCHAR(10), @to_date, 101))

Answer 3

Looking at how Java does it solved my problem.The first 0 is to zero fill and the second number is the number of columns to use.

Run time #%02d: From %s to %s

Returns:

Run time #08: From 03/21/2019 to 04/21/2019
Run time #09: From 04/21/2019 to 05/21/2019
Run time #10: From 05/21/2019 to 06/21/2019
Run time #11: From 06/21/2019 to 07/21/2019

Using:

Run time #%-4d: From %s to %s

left justifies in four columns. Cool!