PHP Help needed

[ginerjm]

That is not the code that I posted for you to try out.

[ginerjm]

I think that quitting would be a good choice.  People are trying to help you but you are reading anything correctly.

[Dealmightyera]

I'm just new to PHP/Mysql and don't think I can go far beyond this level... I'm still learning.

[Dealmightyera]

Thanks @ginerjm It's going thru but how will i set a return when the code has already been used and when it has not been used but exist on the oda table

[Barand]

I would use a single query which checks if the code is used in one table or the other, or both.

Test data

TABLE: tsc                              TABLE: candidates
+----+-----------------+                +---------+-------+--------+
| id | transactioncode |                | regcode | name  | last   |
+----+-----------------+                +---------+-------+--------+
| 10 |               1 |                |       2 | Alma  | Geddon |
| 11 |               2 |                |       4 | Scott | Chegg  |
| 12 |               3 |                |       5 | Sarah | Tonin  |
| 13 |               4 |                +---------+-------+--------+
+----+-----------------+

The query and results

mysql> SELECT a.transactioncode as tsc
    ->      , coalesce(b.regcode, 'NO') as candidates
    -> FROM tsc a
    ->      LEFT JOIN
    ->      candidates b ON a.transactioncode = b.regcode
    -> UNION
    -> SELECT coalesce(a.transactioncode, 'NO') as tsc
    ->      , b.regcode as candidates
    -> FROM candidates b
    ->      LEFT JOIN
    ->      tsc a ON a.transactioncode = b.regcode;
+------+------------+
| TSC  | CANDIDATES |
+------+------------+
| 1    | NO         |
| 2    | 2          |
| 3    | NO         |
| 4    | 4          |
| NO   | 5          |
+------+------------+

Because you are interested in one code at a time, just add WHERE clauses to each half of the UNION. I.E....

SELECT a.transactioncode as TSC
     , coalesce(b.regcode, 'NO') as CANDIDATES
FROM tsc a 
     LEFT JOIN 
     candidates b ON a.transactioncode = b.regcode
WHERE transactioncode = ?
UNION 
SELECT coalesce(a.transactioncode, 'NO') as TSC
     , b.regcode as CANDIDATES
FROM candidates b
     LEFT JOIN 
	 tsc a ON a.transactioncode = b.regcode;
WHERE regcode = ?

Note that the the inputted code is used twice, so your execute command would be

$stmt->execute( [ $code, $code ] );