I'm creating the following trigger:

```
CREATE TRIGGER Trigger_UpdateTrainingDelivery
    AFTER DELETE OR INSERT OR UPDATE OF STARTDATE
    ON TPM_TRAININGPLAN
    BEGIN
      UPDATE TPM_PROJECTVERSION V
        SET TRAININGDELIVERYSTART = (SELECT MIN(STARTDATE) FROM TPM_TRAININGPLAN WHERE PROJECTID=V.PROJECTID AND VERSIONID=V.VERSIONID AND TRAININGPLANTYPE='prescribed')
    END;

```

When I create it, I get a warning:

```
Warnings: ---> 
   W (1): Warning: execution completed with warning
          <--- 

```

However, it's still created it anyway. When I then modify a row in TPM\_TRAININGPLAN, I get an error:

```
>[Error] Script lines: 12-12 ------------------------
 ORA-04098: trigger 'TPMDBO.TRIGGER_UPDATETRAININGDELIVERY' is invalid and failed re-validation
 Script line 12, statement line 1, column 7

```

Is there something wrong with my trigger? I can run the UPDATE statement in the trigger by itself and it runs fine, so I don't think there's anything wrong with that.