I have these values: d1, d45, d79, d33, d100
I want to sort these variables in ascending order from my table.
What is the query to get the output as:
d1
d33
d45
d79
d100
What you want is called a "natural sort". For Microsoft SQL Server 2005, see this question. For other languages, see (for example) this other question.
Sorry, not SQL answer at all. :) For variant with one letter only order by length and alpha.
If you can guarantee a pattern of /\w\d+/ ...
In postgres:
select foo from bar order by cast(substring(foo from 2) as int)
..and similar will exist for other SQL flavours. Expensive mind.
edit: androids solution looks good too:
..order by char_length(foo),foo
If we can assume that the data values only contain the letter d and a numeric value, then you can also use:
select column from YourTable
order by convert(int, replace(column, 'd', ''))
If it contains any other letters, then this method rapidly becomes unusable:
select column from YourTable
order by convert(int,
replace(replace(replace(replace(replace(
column, 'a', ''),
'b', ''),
'c', ''),
'd', ''),
'e', '')
)