Maximum Of VALUE Field Of Each Record With Different POINT-NUMBER?

I need to get the maximum value of the VALUE field of each record with different POINTNUMBER, then do an update on the 2nd table.

table 1
UTCTime TIMESTAMP (6)
INTEGER POINTNUMBER
FLOAT VALUE (126)
INTEGER TLQ

table 2 (idem structure)
UTCTime TIMESTAMP (6)
INTEGER POINTNUMBER
FLOAT VALUE (126)
INTEGER TLQ

Where POINTNUMBER is six thousand different values My query only returns me the maximum of a single record:

SELECT * FROM table1 WHERE value = (SELECT MAX (value) FROM table2);

And the update:
UPDATE table2 SET to a.value = (SELECT MAX (b.value) FROM table2 b);

so does on a single record.That needed to maximize each pointnumber different? I can use a cursor to do this easier?

Insertion should first make a one-time, and then updates every 1 hour