sql - Order VARCHAR AND NUMBER -


this question has answer here:

column : varchar

i have select :

select column table

ae 10000 10005 ad ab ac 10010

and want order them : (number ordered varchar ordered)

select column table order column 

1 - 10000 2 - 10005 3 - 10010 4 - ab 5 - ac 6 - ad 7 - ae

because column character column numbers going ordered binary sort. want order them numerically, means need 2 order clauses

  1. a numeric, numeric characters considered
  2. a standard binary sort
select column_name   table  order case when regexp_like(column_name, '^\d+$') to_number(column_name) end         , column_name

the regular expression

  • ^ - anchor beginning of string
  • \d - match numbers
  • + - match previous expression number of times
  • $ - anchor end of string

it serves enforce numbers exist prior converting column number initial sort.

more generally, it's never wise put numbers , characters in same column, reason you've discovered , because prevents enforcing data type correct.

lastly, consider whether need order query @ all, sorting necessary display purposes or applying business logic "top" n elements of sorted data set.


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