materialized view

[yxez]

Hi friends,

What is the difference of the 2 commands?

1.> create materialized view oe.emp
as select * from oe.emp@ora1.world;

2.> create materialized view oe.emp refresh fast
as select * from oe.emp@ora1.world;

What type of refresh does #1 use by default?
is it REFRESH SLOW?

thanks a lot

[CarlosAL]

>"What type of refresh does #1 use by default? is it REFRESH SLOW?"

No. It is REFRESH FORCE, which will issue a REFRESH FAST if possible (MATERIALIZED VIEW LOG exists, among others) or REFRESH COMPLETE.

HTH.

Cheers.

Carlos.

[yxez]

Thanks dear...

I got confused about this command also.

> create materialized view oe.emp
REFRESH FAST START WITH SYSDATE NEXT SYSDATE + 1/24
as select * from oe.emp@ora1.world;

Is this a correct syntax? Does it refresh my view every hour
for eternity? or just the next 1 hr one time only?

...or do i need to run this command>

DBMS_DEFER_SYS.SCHEDULE_PUSH (
destination => 'ora1.world',
interval => 'SYSDATE + (1/24)', -- you set the time interval here
next_date => SYSDATE,
parallelism => 4,
execution_seconds => 0,
delay_seconds => 55);
END;
/

Thanks a lot

[CarlosAL]

>>"Is this a correct syntax? Does it refresh my view every hour
for eternity? or just the next 1 hr one time only?"

It is correct... as long as you have a materialized view log for the master table.

It will refresh the MW one hour after it finishes refreshing each time.

HTH.

Cheers.

Carlos.