Select a row based on conditions for next row - mysql

Question

Here is a part of my MySQL Table:
| id | opentrap | openrect | lampgroen | lamprood | closeout | openout | limitswitchclose | limitswitchopen | traploop | photocells | rectloop | DateTime | milliseconds |
| 92 | 0 | 0 | 1 | 1 | 0 | 1 | 0 | 1 | 1 | 1 | 1 | 2018-11-09 13:56:41 | 654 |
| 93 | 0 | 0 | 1 | 1 | 0 | 1 | 0 | 1 | 1 | 1 | 1 | 2018-11-09 13:56:42 | 262 |
| 94 | 0 | 0 | 1 | 1 | 0 | 1 | 0 | 1 | 0 | 0 | 1 | 2018-11-09 13:56:42 | 561 |
| 95 | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 2018-11-09 13:56:45 | 83 |
| 96 | 0 | 0 | 1 | 1 | 0 | 1 | 0 | 1 | 1 | 0 | 0 | 2018-11-09 13:56:46 | 189 |
| 97 | 0 | 0 | 1 | 1 | 0 | 1 | 0 | 1 | 1 | 1 | 0 | 2018-11-09 13:56:47 | 402 |
| 98 | 0 | 0 | 1 | 1 | 0 | 1 | 0 | 1 | 0 | 1 | 1 | 2018-11-09 13:56:48 | 611 |
| 99 | 0 | 0 | 1 | 1 | 0 | 1 | 0 | 1 | 0 | 0 | 1 | 2018-11-09 13:56:48 | 916 |
I want to select a row based on alot of conditions and based if the next row has
traploop = 1 or rectloop = 1
The query I want to use looks like this (but I can't figure out how to write a condition for the next row):
SELECT *
FROM table
WHERE closeout = 0
AND openout = 0
AND lampgroen = 1
AND lamprood = 1
AND limitswitchopen = 1
AND NEXTROW: traploop = 1
OR rectloop = 1;
This should give me:
| 95 | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 2018-11-09 13:56:45 | 83 |

Answer 1

Here is one approach, using correlated subqueries:
SELECT *
FROM yourTable t1
WHERE closeout = 0 AND openout = 0 AND lampgroen = 1 AND lamprood = 1 AND
limitswitchopen = 1 AND
((SELECT t2.traploop FROM yourTable t2
WHERE t2.id > t1.id ORDER BY t2.id LIMIT 1) = 1 OR
(SELECT t2.rectloop FROM yourTable t2
WHERE t2.id > t1.id ORDER BY t2.id LIMIT 1) = 1);
Demo
This approach is robust to the possibility that the id values may not be continuous. The only requirement for the "next" row is that it have the next highest id value from the current row.

Answer 2

This is what you need:
SELECT t0.*
FROM
table t0
INNER JOIN
table t1
ON t0.id + 1 = t1.id
WHERE
t0.closeout = 0 AND
t0.openout = 0 AND
t0.lampgroen = 1 AND
t0.lamprood = 1 AND
t0.limitswitchopen = 1 AND
(t1.traploop = 1 OR t1.rectloop = 1);

Answer 3

You can get the "next" row using join -- assuming that "next" is based on id and that has no gaps:
select . . .
from t join
tnext
on tnext.id = t.id + 1
where . . .;
You can then apply the conditions to either t or tnext.
In MySQL 8+, lead() would be a better alternative.

Answer 4

You can try with Correlated Subquery with Exists()
SELECT t1.*
FROM table AS t1
WHERE t1.closeout = 0 AND
t1.openout = 0 AND
t1.lampgroen = 1 AND
t1.lamprood = 1 AND
t1.limitswitchopen = 1 AND
EXISTS (SELECT 1
FROM table AS t2
WHERE t2.id = t1.id + 1 AND
(t2.traploop = 1 OR t2.rectloop = 1)
)
PS: This assumes that there are no gaps in id column

Answer 5

A simple query that uses correlated sub queries but works if ids have gaps is this:
SELECT *
FROM t AS curr
WHERE closeout = 0 AND openout = 0 AND lampgroen = 1 AND lamprood = 1 AND limitswitchopen = 1
AND 1 = (
SELECT CASE WHEN traploop = 1 OR rectloop = 1 THEN 1 END
FROM t AS next
WHERE id > curr.id
ORDER BY id
LIMIT 1
)
Demo on DB Fiddle