I've just wasted the past two hours of my life trying to create a table with an auto incrementing primary key bases on this tutorial, The tutorial is great the issue I've been encountering is that the Create Target fails if I have a column which is a timestamp and a table that is called timestamp in the same table...
Why doesn't oracle flag this as being an issue when I create the table?
Here is the Sequence of commands I enter:
Creating the Table:
CREATE TABLE myTable
(id NUMBER PRIMARY KEY,
field1 TIMESTAMP(6),
timeStamp NUMBER,
);
Creating the Sequence:
CREATE SEQUENCE test_sequence
START WITH 1
INCREMENT BY 1;
Creating the trigger:
CREATE OR REPLACE TRIGGER test_trigger
BEFORE INSERT
ON myTable
REFERENCING NEW AS NEW
FOR EACH ROW
BEGIN
SELECT test_sequence.nextval INTO :NEW.ID FROM dual;
END;
/
Here is the error message I get:
ORA-06552: PL/SQL: Compilation unit analysis terminated
ORA-06553: PLS-320: the declaration of the type of this expression is incomplete or malformed
Any combination that does not have the two lines with a the word "timestamp" in them works fine. I would have thought the syntax would be enough to differentiate between the keyword and a column name.
As I've said I don't understand why the table is created fine but oracle falls over when I try to create the trigger...
CLARIFICATION
I know that the issue is that there is a column called timestamp which may or may not be a keyword. MY issue is why it barfed when I tried to create a trigger and not when I created the table, I would have at least expected a warning.
That said having used Oracle for a few hours, it seems a lot less verbose in it's error reporting, Maybe just because I'm using the express version though.
If this is a bug in Oracle how would one who doesn't have a support contract go about reporting it? I'm just playing around with the express version because I have to migrate some code from MySQL to Oracle.
A trigger fired by an INSERT statement has meaningful access to new column values only. Because the row is being created by the INSERT operation, the old values are null. A trigger fired by an UPDATE statement has access to both old and new column values for both BEFORE and AFTER row triggers.
Your insert will either entirely succeed (insert into t1 and into t2 succeed) or neither will - both will "fail" because the statement itself failed. So, after your insert, if the trigger failed - the database will look like your insert never ever happened.
Creating Triggers CREATE [OR REPLACE] TRIGGER trigger_name − Creates or replaces an existing trigger with the trigger_name. {BEFORE | AFTER | INSTEAD OF} − This specifies when the trigger will be executed. The INSTEAD OF clause is used for creating trigger on a view.
A new column value can be assigned in a BEFORE row trigger, but not in an AFTER row trigger (because the triggering statement takes effect before an AFTER row trigger is fired). If a BEFORE row trigger changes the value of new .
There is a note on metalink about this (227615.1) extract below:
# symptom: Creating Trigger fails
# symptom: Compiling a procedure fails
# symptom: ORA-06552: PL/SQL: %s
# symptom: ORA-06553: PLS-%s: %s
# symptom: PLS-320: the declaration of the type of this expression is incomplete or malformed
# cause: One of the tables being references was created with a column name that is one of the datatypes (reserved key word). Even though the field is not referenced in the PL/SQL SQL statements, this error will still be produced.
fix:
Workaround:
1. Rename the column to a non-reserved word.
2. Create a view and alias the column to a different name.
TIMESTAMP is not listed in the Oracle docs as a reserved word (which is surprising).
It is listed in the V$RESERVED_WORDS data dictionary view, but its RESERVED flag is set to 'N'.
It might be a bug in the trigger processing. I would say this is a good one for Oracle support.
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