【备忘】SQL Server的一个有意思的功能

declare @x as xml,
		@t as varchar(max),
		@b as varbinary(max),
		@64 as varchar(max);
select
	@x = '',
	@t = 'GIF89',
	@b = cast(@t as varbinary(max));
set	@64 = @x.value('sql:variable("@b")', 'varchar(max)');

select
	@t, @b, @64,
	@x.value('sql:variable("@64")', 'varchar(max)'),
	@x.value('sql:variable("@64")', 'varbinary(max)'),
	cast(@x.value('sql:variable("@64")', 'varbinary(max)') as varchar(max))

转载于:https://www.cnblogs.com/NanaLich/archive/2010/12/20/t-sql-base64.html