After update trigger help

Question

I am getting a trigger error when updating a table. Here is the trigger :
CREATE OR REPLACE TRIGGER "SCHEMA"."UPD_SOMETABLE" AFTER
UPDATE ON "SCHEMA"."UPD_SOMETABLE" REFERENCING OLD AS OLD NEW AS NEW FOR EACH ROW BEGIN
UPDATE "SCHEMA"."UPD_SOMETABLE" SET "DATE_UPDATED" = SYSDATE
END;
ALTER TRIGGER "SCHEMA"."UPD_SOMETABLE" ENABLE;
The error :
SQL Error: ORA-04098: trigger 'SCHEMA.UPD_SOMETABLE' is invalid and failed re-validation
04098. 00000 - "trigger '%s.%s' is invalid and failed re-validation"
*Cause:    A trigger was attempted to be retrieved for execution and was
found to be invalid. This also means that compilation/authorization
failed for the trigger.
*Action:   Options are to resolve the compilation/authorization errors,
disable the trigger, or drop the trigger.

Answer 1

The syntax error is the lack of a semicolon after SYSDATE. There is also an error that the table name and trigger name are the same but I'm guessing that's something you did in sanitizing the code before posting it
Once you fix the syntax error, however, you're very likely to get a runtime mutating table error.
If your intention is to set the DATE_UPDATED column to SYSDATE for each row that is updated, you'd need to use a before update trigger, you'd adjust the :new.date_updated, and you'd fix the syntax error. Something like
CREATE OR REPLACE TRIGGER trigger_name
  BEFORE UPDATE ON table_name
  FOR EACH ROW
BEGIN
  :new.date_updated := sysdate;
END;If you are trying to do something other than what I guessed above, please let us know what you are trying to get the trigger to do.
Justin