Hello Jupiter;

Sorry you are forced to use something as great as Firebird :-). I assume LAST_MODIFIED_ON is a TIMESTAMP field in your table and is being updated via a trigger or some other mechanism as records are modified. Your DATEDIFF syntax is incorrect; try:

... WHERE LICENSE_PLATE_NO<>'No plate found' AND DATEDIFF(second,LAST_MODIFIED_ON,current_timestamp)<120

or

... WHERE LICENSE_PLATE_NO<>'No plate found' AND DATEDIFF(minute,LAST_MODIFIED_ON,current_timestamp)<2


Regards,

Jonathan

--- In firebird-support@yahoogroups.com, Jupiter Punungwe <punungwe.tech@...> wrote:
>
> I am running this query
>
> SELECT LICENSE_PLATE_NO, IMAGE_NAME FROM table WHERE (LICENSE_PLATE_NO<>'No
> plate found') AND (DATEDIFF(second FROM LAST_MODIFIED_ON TO
> current_time)<120)
>
> the aim being to find all records modified in the last two minutes.
>
> I get the error message
>
> '[blah blah blah] expression evaluation not supported.'
>
> Does this mean I cannot put a function in a Firebird SQL statement? I can
> do this in MySQL and SQL Server without any problem. In this particulat
> project, I am forced to use Firebird for legacy reasons.
>
> Regards
> Jupiter
>
>
> [Non-text portions of this message have been removed]
>