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