tsql - SQL SERVER - Understanding how MIN(text) works -

i'm doing little digging , looking explanation on how sql server evaluates min(varchar).

i found remark in bol: min finds lowest value in collating sequence defined in underlying database

so if have table has 1 row following values:

data  aa ab ac 

doing select min(data) return aa. want understand why behind , understand bol little better.

thanks!

it's determined collation (sort order). cultures collation order same alphabetical order in english alphabet so:

• 'aa' < 'ab'
• 'aa' < 'ac'
• 'ab' < 'ac'

therefore 'aa' minimum value. other cultures may not hold. example danish collation return 'ab' minimum because 'aa' > 'ab'. because 'aa' treated equivalent 'Å' last letter in danish alphabet.

 select min(s collate danish_norwegian_ci_as) table1;  min_s ab 

to "ordinary" sort order use latin1_general_bin collation:

 select min(s collate latin1_general_bin) table1;  min_s aa 

to reproduce result can create test table:

 create table table1 (s varchar(100)); insert table1 (s) values ('aa'), ('ab'), ('ac');