Using Like operator in SQL Server does 'Ename like '[A-Z]%' and 'Ename like '[a-z]%' mean same?

Question

I am little bit confused for the Question stating that "First character should be capital in a column".

I tried using LIKE function for the Question "First character should be '+' or numeric" as select * from emp where mobile like '+%' or mobile like '[0-9]%';

Answer 1

As I mention in the comment, this all depends on the collation you are using. If you are using a case insensitive collation then LIKE '[AZ]' and LIKE '[az]' are synonyms as for comparison purposes the case of the letter doesn't matter. For a case sensitive or binary collation, however, this is not the case and the 2 expressions will result in different results.

So, for 3 example collations you can see that one returns 1 , while the other two return 0 :

SELECT CASE 'A' COLLATE Latin1_General_CI_AI WHEN 'a' COLLATE Latin1_General_CI_AI THEN 1 ELSE 0 END AS CaseInsensitiveCollation,
       CASE 'A' COLLATE Latin1_General_CS_AI WHEN 'a' COLLATE Latin1_General_CS_AI THEN 1 ELSE 0 END AS CaseSensitiveCollation,
       CASE 'A' COLLATE Latin1_General_BIN WHEN 'a' COLLATE Latin1_General_BIN THEN 1 ELSE 0 END AS BinaryCollation;