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sql-serverreplacehexnul

In SQL Server, replace a Char(0), the null character, embedded in a string with its hex code

What is a construct in SQL Server T-SQL that will replace a Char(0), the null character, embedded in a string with its hex code?

I.e.

 REPLACE('t'+Char(0)+'t', Char(0), REPLACE(master.dbo.fn_varbintohexstr(0), '000000', ''))

does not return 't0x00t', what does? (This does already work for 1 through 31.)

This question has answers explaining the problem is the Collation.

This answer shows master.dbo.fn_varbintohexstr(0) will return 0x00000000.

When I manually simplified the inner Replace to '0x00', just adding a Collate clause did get it to work, like the answers to the above question suggested, but I can't find a version that works for the full expression (which then could be used for all n, 0 to 31, skipping 9, 10 and 13).

Solution

  • What you want might be this.

    SELECT REPLACE('t'+Char(0)+'t', Char(0), CONVERT(VARCHAR(10),REPLACE(master.dbo.fn_varbintohexstr(0), '000000', '')))

    You need to convert it explicitly to VARCHAR

    and if you want the full expression remove inner replace

    SELECT REPLACE('t'+Char(0)+'t', Char(0), CONVERT(VARCHAR(10),master.dbo.fn_varbintohexstr(0)))