Mysql Left Join of 3 tables and a one being joined twice - mysql

Question

I need to do a join of 3 tables.
They all have an ID value, the issue is:
Table 1
Is the main one, name : cnpj_cnae and the ID is CNPJ_CNAE
Table 2
I need to get four columns from this one (Up to here I already got it).
The ID here is CNPJ_CNAE
Table 3
Here's the issue. For each ID value on table 1 I can have more than 1 even 10 on this table. I need to get 4 columns from ONLY THE FIRST TWO of this table.
The ID here is CNPJ_SOCIO
The finishing table would need to look like
ID INFOTABLE1 INFOTABLE2 INFOTABLE3ROW1 INFOTABLE3ROW2
I have tried some joins, but being a relative newbie with mysql I am suffering >.<
I have tried to do this:
CREATE TABLE cnpj_cnae_emp_test3 AS (
SELECT
`cnpj_cnae_test2`.*,
`cnpj_soci`.NOME_SOCIO,`cnpj_soci`.CNPJ_CPF_SOCI,`cnpj_soci`.ID_QUALIFICACAO_REP,`cnpj_soci`.DESC_QUALIFICACAO_REP,
`cnpj_emp_02`.MUNICIPIO,`cnpj_emp_02`.BAIRRO,`cnpj_emp_02`.TIPO_LOGRADOURO,`cnpj_emp_02`.LOGRADOURO,`cnpj_emp_02`.NUMERO,`cnpj_emp_02`.COMPLEMENTO
FROM `cnpj_cnae_test2`, `cnpj_soci`, `cnpj_emp_02`
WHERE `cnpj_cnae_test2`.CNPJ_CNAE = `cnpj_soci`.CNPJ_SOCIO AND `cnpj_cnae_test2`.CNPJ_CNAE = `cnpj_emp_02`.CNPJ
);
The issue is this will generate extra rows for every SOCI where instead of 1 soci on each one I need 2 socis on each line.
Table 1:
Layout of CNAE table
Table 2:
Layout of EMP table
Table 3:
Layout of Socio table
The resulting table would look like this:
More detailed end result Final layout with descriptions
Layout of result
In the end this by Owl was exactly what I needed:
WITH soci_partition AS (
SELECT CNPJ_SOCIO
,NOME_SOCIO
,CNPJ_CPF_SOCIO
,ID_QUALIFICACAO
,DESC_QUALIFICACAO_SOCIO
,row_number() OVER (PARTITION BY CNPJ_SOCIO ORDER BY IDX ASC) AS rownum
FROM cnpj_soci
)
SELECT * -- add actual columns
FROM cnpj_cnae_test2 AS cnae
INNER JOIN cnpj_emp_02 AS emp -- left join instead? depends on table structure
ON cnae.ID_CNAE = emp.IDX
LEFT JOIN soci_partition AS soci1
ON soci1.CNPJ_SOCIO = cnae.CNPJ_CNAE and soci1.rownum = 1
LEFT JOIN soci_partition AS soci2
ON soci2.CNPJ_SOCIO = cnae.CNPJ_CNAE and soci2.rownum = 2

Answer 1

Not sure if I got the joins/partition right, the foreign keys weren't clear.
Even if it's not perfect, hopefully this explains the general theory. Please edit in your correct answer if you end up debugging.
Also don't use old-style joins. You'll immediately fail interviews on that alone; they were deprecated 25 years ago.
WITH soci_partition AS (
SELECT CNPJ_SOCIO
,NOME_SOCIO
,CNPJ_CPF_SOCIO
,ID_QUALIFICACAO
,DESC_QUALIFICACAO_SOCIO
,row_number() OVER (PARTITION BY CNPJ_SOCIO ORDER BY IDX ASC) AS rownum
FROM cnpj_soci
)
SELECT * -- add actual columns
FROM cnpj_cnae_test2 AS cnae
INNER JOIN cnpj_emp_02 AS emp -- left join instead? depends on table structure
ON cnae.ID_CNAE = emp.IDX
LEFT JOIN soci_partition AS soci1
ON soci1.CNPJ_SOCIO = cnae.CNPJ_CNAE and soci1.rownum = 1
LEFT JOIN soci_partition AS soci2
ON soci2.CNPJ_SOCIO = cnae.CNPJ_CNAE and soci2.rownum = 2

Answer 2

Give a try to below query
select * from cnae t1
left join emp t2 on t1.cnpj_cnae = t2.cnpj
left join socio t3 on t1.cnpj_cnae = t2.cnpj_socio
group by idx_cnae ;