Randomly select fields where few condition met - php

Question

Here is the table-
+----+---------+--------+
| id | letters | status |
+----+---------+--------+
| 1 | A | 0 |
| 2 | B | 1 |
| 3 | C | 0 |
| 4 | D | 0 |
| 5 | E | 1 |
| 6 | F | 1 |
| 7 | G | 0 |
| 8 | H | 0 |
+----+---------+--------+
Its need to finds records with the conditions below-
select letters with LIMIT 3
ORDER is RAND()
status true or false both need to present but at-least a presents of
letters with status TRUE but not more then 2
Desire results could be as-
+---------+--------+
| letters | status |
+---------+--------+
| B | 1 |
| E | 1 |
| H | 0 |
+---------+--------+
+---------+--------+
| letters | status |
+---------+--------+
| C | 0 |
| E | 1 |
| H | 0 |
+---------+--------+
But not as-
+---------+--------+
| letters | status |
+---------+--------+
| C | 0 |
| G | 0 |
| H | 0 |
+---------+--------+
+---------+--------+
| letters | status |
+---------+--------+
| B | 1 |
| E | 1 |
| F | 1 |
+---------+--------+
Anyone please help.

Answer 1

Here is a solution in Postgres as requested in the comments.
Assuming status to be NOT NULL.
Assuming at least one row with status FALSE and one with status TRUE exist at all times.
WITH cte AS (
(
SELECT id, letters, status
FROM tbl
WHERE status -- 1 row with status true
ORDER BY random()
LIMIT 1
)
UNION ALL
(
SELECT id, letters, status
FROM tbl
WHERE NOT status -- 1 row with status false
ORDER BY random()
LIMIT 1
)
)
SELECT * FROM cte
UNION ALL -- add another random row
(
SELECT id, letters, status
FROM tbl
LEFT JOIN cte c USING (id)
WHERE c.id IS NULL -- don't select row twice
ORDER BY random()
LIMIT 1
)
ORDER BY random(); -- order 3 rows randomly
MySQL does not supports CTEs.
All parentheses are necessary. Details:
PostgreSQL combine multiple select statements
This is not very efficient for big tables. For better performance consider this related answer:
Best way to select random rows PostgreSQL
If status TRUE and FALSE are not extremely unbalanced, I would write a plpgsql function that loops through the randomly sorted table (or selection like in the the linked answer) until I have three rows with at least one of each status. Would be much faster.