Is it possible to pass a built in function as an argument to a trigger?

Question

I ask this question in light of the following trigger producing this error:

ERROR: syntax error at or near "("
LINE 5: ...cessBlogPostApproval"('Blog Post Approval', concat('Your blo...
^

The trigger in question:

CREATE TRIGGER "processBlogPostApproval_AFTER_INSERT"
    AFTER INSERT
    ON public."ApprovedBlogPosts"
    FOR EACH ROW
    EXECUTE PROCEDURE public."processBlogPostApproval"('Blog Post Approval', concat('Your blog post, "', SELECT "Title" FROM public."BlogPosts" WHERE "PostID" == NEW."PostID", '"has been approved.'));

The problem seems to be arising due to the fact that I passed a concatenation function as my second argument, or rather, that I did not pass it correctly. Would appreciate your assistance in identifying which of the two is the cause of the problem.

Answer 1

The CREATE TRIGGER documentation says:

arguments: An optional comma-separated list of arguments to be provided to the function when the trigger is executed. The arguments are literal string constants. Simple names and numeric constants can be written here, too, but they will all be converted to strings.

You cannot do any processing before the function is called; you have to put all the logic into the trigger function.