How to make a JOIN with table containing attribute value zero? - mysql

Question

I have a table that I defined one column to receive zero 0 as value. I did this because zero 0 represents all values. The table's name is agendas and the column it's turmas_id, this column has relationship with table turmas but turmas_id in agendas it's not a foreignkey because I can add 0 as saied before.
The problem is when I make a JOIN using these tables because I need return all attributes with zero value and valid keys added in table turmas.
I tried use LEFT JOIN and INNER JOIN but the result it's not what I wait. I can use JOIN if id exists in table turmas and table agendas because it's a valid foreign key but I can't return other values with 0 in agendas attribute turmas_id and this is exactly what I need.
How could I do this ?
I need display this result
//table agendas
-----------------------------------------
turmas_id | descricao
-----------------------------------------
0 | this attribute contain zero and it's not exists in table turmas
16 | table turmas contain id 16 it is a foreign key
0 | this attribute contain zero and it's not exists in table turmas
23 | table turmas contain id 23 it is a foreign key
SQL
$agendamentos = $this->Agenda->query("SELECT * FROM responsavel_alunos RespAlunos "
. "INNER JOIN pessoas Responsavel ON (Responsavel.id = RespAlunos.pessoas_id) "
. "INNER JOIN pessoas Aluno ON (Aluno.id = RespAlunos.pessoas_id1) "
. "INNER JOIN matriculas Matricula ON (Matricula.pessoas_id = Aluno.id) "
. "RIGHT JOIN turmas Turma ON (Turma.id = Matricula.turmas_id OR Turma.id = 0) "
. "INNER JOIN escolas Escola ON (Escola.id = Matricula.escolas_id) "
. "INNER JOIN agendas Agenda ON (Agenda.turmas_id = Turma.id) "
. "WHERE Responsavel.id = ? ORDER BY Agenda.created DESC "
, array($id)); //id do responsavel
Model
JSON result
{
"status": "1",
"result": [
{
"RespAlunos": {
"id": "5",
"pessoas_id": "8",
"pessoas_id1": "9",
"created": "2015-09-21 10:25:46",
"modified": "2015-09-21 10:25:46"
},
"Responsavel": {
"id": "8",
"nome": "responsavel ",
"email": "responsavel #hotmail.com",
"tipopessoas_id": "3",
"status": "1",
"created": "2015-09-21 10:17:17",
"modified": "2015-09-21 10:17:17"
},
"Aluno": {
"id": "9",
"nome": "aluno",
"email": "aluno#gmail.com",
"tipopessoas_id": "1",
"status": "1",
"created": "2015-09-21 10:18:41",
"modified": "2015-09-21 10:18:41"
},
"Matricula": {
"id": "6",
"referencia": "238",
"pessoas_id": "9",
"turmas_id": "4",
"escolas_id": "2",
"status": "1",
"created": "2015-09-21 10:35:08",
"modified": "2016-02-18 10:51:20"
},
"Turma": {
"id": "4",
"descricao": "4º ano",
"created": "2015-09-21 10:31:32",
"modified": "2015-09-21 10:31:32"
},
"Escola": {
"id": "2",
"descricao": "Santa Luz Unidade 2",
"created": "2015-09-17 23:09:38",
"modified": "2015-09-17 23:09:38"
},
"Agenda": {
"id": "34",
"data": "2016-02-29 14:40:00",
"descricao": "<p>teste 1</p>\r\n",
"escolas_id": "2",
"turmas_id": "4",
"created": "2016-02-29 14:40:21",
"modified": "2016-02-29 14:40:21"
}
},
{
"RespAlunos": {
"id": "5",
"pessoas_id": "8",
"pessoas_id1": "9",
"created": "2015-09-21 10:25:46",
"modified": "2015-09-21 10:25:46"
},
"Responsavel": {
"id": "8",
"nome": "responsavel ",
"email": "responsavel #hotmail.com",
"tipopessoas_id": "3",
"status": "1",
"created": "2015-09-21 10:17:17",
"modified": "2015-09-21 10:17:17"
},
"Aluno": {
"id": "9",
"nome": "aluno",
"email": "aluno#gmail.com",
"tipopessoas_id": "1",
"status": "1",
"created": "2015-09-21 10:18:41",
"modified": "2015-09-21 10:18:41"
},
"Matricula": {
"id": "6",
"referencia": "238",
"pessoas_id": "9",
"turmas_id": "4",
"escolas_id": "2",
"status": "1",
"created": "2015-09-21 10:35:08",
"modified": "2016-02-18 10:51:20"
},
"Turma": {
"id": "4",
"descricao": "4º ano",
"created": "2015-09-21 10:31:32",
"modified": "2015-09-21 10:31:32"
},
"Escola": {
"id": "2",
"descricao": "Santa Luz Unidade 2",
"created": "2015-09-17 23:09:38",
"modified": "2015-09-17 23:09:38"
},
"Agenda": {
"id": "27",
"data": "2016-02-29 08:24:00",
"descricao": "descricao",
"escolas_id": "2",
"turmas_id": "4",
"created": "2016-02-29 08:25:20",
"modified": "2016-02-29 08:25:20"
}
}
]
}

Answer 1

try to use IN ? instead of using = ? in your WHERE clause since your using an array variable

Answer 2

Can you try RIGHT JOIN instead?
"RIGHT JOIN turmas Turma ON (Turma.id = Matricula.turmas_id OR Turma.id = 0)"
because TABLE1 LEFT JOIN TABLE2 means all rows from TABLE1 will be selected, even if there are no matching rows in TABLE2.
RIGHT JOIN is the opposite of it. So use RIGHT JOIN so that you can return your TURMA records based from the ON condition, even if there are no matching records from the preceding table.

Answer 3

Try this one.
$agendamentos = $this->Agenda->query("SELECT * FROM responsavel_alunos RespAlunos "
. "INNER JOIN pessoas Responsavel ON (Responsavel.id = RespAlunos.pessoas_id) "
. "INNER JOIN pessoas Aluno ON (Aluno.id = RespAlunos.pessoas_id1) "
. "INNER JOIN matriculas Matricula ON (Matricula.pessoas_id = Aluno.id) "
. "(SELECT turmas as turma WHERE (turma.id = Matricula.turmas_id OR turma.id = 0)) AS TURMA"
. "INNER JOIN escolas Escola ON (Escola.id = Matricula.escolas_id) "
. "INNER JOIN agendas Agenda ON (Agenda.turmas_id = Turma.id) "
. "WHERE Responsavel.id IN ? ORDER BY Agenda.created DESC "
, array($id)); //id do responsavel