MariaDB 中的 INITCAP

Question

I am currently trying to check that every values that are inserted into my MariaDB table the 1st letter of every word in uppercase, so I tried to use CONSTRAINT nombreok CHECK (INITCAP(nombre_director) = nombre_director)); but it doesn't works because it gives me an error saying that function INITCAP() cannot be used in a CHECK... what can I do to solve it?

Answer 1

I think initcap() is not deterministic because the results may depend on the default collation of the database (under some circumstances).

You can ensure that the first characters are capitalized using:

CONSTRAINT nombreok CHECK (not (nombre_director collate latin1_general_cs) REGEXP '(^|[[:space:]])[[:lower:]]')

Here is a db<>fiddle.

If you want to check the lower case as well:

CONSTRAINT nombreok CHECK ((nombre_director collate latin1_general_cs) REGEXP '^([[:upper:]][[:lower:]]+([[:space:]]+|$))+$')

However, you might want to extend this beyond just alphabetical characters.

Here is a db<>fiddle for this.