内容在PostgreSQL中是否具有小写字母

Question

How can we check In PostgreSQL or SQL:

A string saved in database to lowercase OR uppercase?

For example, I have five records in my database table and I want to fetch only those records that have lowercase characters.

Here is my content table and id's in primary key

id    Content

 1     TEST
 2     Test
 3     TEst
 4     TESt
 5     TEST01

I need to fetch id 2,3,4 respectively which contains context value in lowercase.

Answer 1

Add the following WHERE clause:

WHERE content <> upper(content)

That will only retrieve the rows that contain lower case characters.