Laravel raw select with avg - cannot display fetched data - mysql

Question

I have Laravel project and I want to fetch avg time. Select statement is correct but I can not display data because I get error: Array to string conversion
This is my code:
$limit = (int)$this->argument('distance');
$avgTimeBetweenBlocks = DB::select('SELECT AVG(b.timediff)
FROM
(
SELECT a.created_at, a.created_at_end, AVG(TIME_TO_SEC(TIMEDIFF(a.created_at, a.created_at_end))) AS timediff
FROM
(
SELECT created_at,
(
SELECT max( created_at)
FROM block_differences bd1
WHERE bd1.created_at < bd.created_at
) as created_at_end
FROM block_differences bd
limit :limit
) a
WHERE a.created_at_end is not null
GROUP BY a.created_at, a.created_at_end
) b', ['limit' => $limit] )->get();
echo json_decode(json_encode($avgTimeBetweenBlocks[0]), true);
$this->info("avgTimeBetweenBlocks {$avgTimeBetweenBlocks[0]} seconds");
I tried to display value in different way, but all the time I get the same result.

Answer 1

You're trying to echo an array here json_decode will convert it an array so echo will not work. use print_r instead of echo
print_r(json_decode(json_encode($avgTimeBetweenBlocks[0]), true));
Edit :- Array ( [AVG(b.timediff)] => 139.38775510 )
you've to change your query. check here I give you an example below.
$avgTimeBetweenBlocks = DB::select('SELECT AVG(b.timediff) as avgtimediff
FROM
(
SELECT a.created_at, a.created_at_end, AVG(TIME_TO_SEC(TIMEDIFF(a.created_at, a.created_at_end))) AS timediff
FROM
(
SELECT created_at,
(
SELECT max( created_at)
FROM block_differences bd1
WHERE bd1.created_at < bd.created_at
) as created_at_end
FROM block_differences bd
limit :limit
) a
WHERE a.created_at_end is not null
GROUP BY a.created_at, a.created_at_end
) b', ['limit' => $limit] )->get();
$response = json_decode(json_encode($avgTimeBetweenBlocks[0]), true);
echo $response['avgtimediff'];