Re: PL/PGSQL + inserts+updates+limit - Postgres 9.3

Hi guys,

-

The function works... All the data is updated as expected. However, when
I call the function for the second time, it touches the rows that had
already been touched by the previous call....
-

It triplicate ( LIMIT 3 ) the records.

*Question:*

How can I make the function to gets the next 3 rows and not use the same
rows that have been used before?

Function updated:

CREATE or REPLACE FUNCTION function_data_1()
RETURNS SETOF bigint AS $$
declare
row record;
BEGIN
-- copying the data to the backup table (not the blobs)-- Limiting in
5000 rows each callFOR row IN EXECUTE '
SELECT
t1.file_id
FROM
table1 t1
JOIN
table3 t3 ON t3.file_id = t1.file_id
ORDER BY 1 LIMIT 3 '
LOOP
-- Creating the backup table with the essential dataINSERT INTO table2
(note_id, size, file_id, full_path)
(
SELECT
t1.note_id,
t1.size,
t1.file_id,
t1.full_path
FROM
table1 t1
JOIN
table3 t3 ON t3.file_id = t1.file_id
WHERE
t1.file_id = row.file_id
);
-- copying the blobs to the table above table2
UPDATE junk.table2 t2 SET data =
(
SELECT
o1.data
FROM
original_table1_b o1
JOIN
table3 t3 ON t3.file_id = o1.file_id
WHERE
t3.migrated = 0
AND
t2.file_id = o1.file_id
AND
o1.file_id = row.file_id
)
WHERE t2.file_id = row.file_id;
-- updating the migrated column from 0 to 1
UPDATE
table3 t2
SET
migrated = 1
WHERE
t2.file_id = row.file_id
AND
migrated = 0;
-- set the blobs as null
UPDATE
original_table1_b o1
SET
data = NULL
WHERE
o1.file_id = row.file_id;END LOOP;
END
$$ language 'plpgsql';