Php MYSQL query several tables

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-1

Good, I’m having difficulty showing the data of a database using 3 tables.

<?php
include("conectar.php");

$quantidade = 1;
$pagina = (isset($_GET['pagina'])) ? (int)$_GET['pagina'] : 1;
$inicio = ($quantidade * $pagina)-$quantidade;  
$sql = "Select * From tb_trabalhador order by id asc LIMIT $inicio, $quantidade";
$qr = mysql_query($sql) or die (mysql_error());
    while($exibe = mysql_fetch_array($qr)){

I have 2 more tables to display the data there. I did the test with only two tables and also does not show me the entered data

 SELECT * FROM tb_trabalhador
 INNER JOIN tb_detalhe_trabalhador ON Tb_trabalhador.id     =tb_detalhe_trabalhador.tb_trabalhador_id;

I tried Left and Right and displays the data from the respective tables. I wonder if you can help me with this problem?

php mysql

  • this page has some examples http://blog.thiagobelem.net/relations-tabelas-no-mysql/

  • 2

    As much as some have understood your problem, it is unclear what you are asking. Leave on record what you are needing.

  • I’ve already made changes and I hope it’s clearer now my doubt

  • @user3253195 As far as you can understand, you want to make a Join with the 3 tables. The problem would not be the PHP code. I believe that the question as a whole is not very clear from the words used, such as the term "call tables". Also, you say that the result of your attempt was 0 (zero), but what does that mean? Zero records? Sum equal to zero? Where’s your Join attempt? I think your question was closed because people couldn’t interpret what you said. If I understand correctly, I suggest editing again, including the title, for something related to SQL and Joins.

3 answers

3

Use a Join to join the tables and access all the fields you need:

SELECT * FROM tb_trabalhador as t
INNER JOIN tb_equipamentos as e ON t.id = e.trabalhador_id
INNER JOIN tb_detalhe_trabalhador as d ON t.id = d.tb_trabalhador_id

instead of the asterisk * put the required fields in the format tabela.nome_do_campo or alias.nome_do_campo

Ex: 

SELECT e.marca, e.modelo, t.nome, t.matricula, d.outro_campo FROM ....
INNER ....

Related content: difference between INNER X OUTER

  • does not need the Inner Join

  • need what in place? did not understand your comment

  • Making one select to make the other is not feasible when you can use the @Silvio Andorinha joints. The bank will work much faster with the join than separate equal in the link you posted to him in the comment. However it is a way to do too, is at his discretion.

  • @lionbtt see my answer http://answall.com/questions/6706/php-query-varias-tabelas/6715#6715

  • only a question. ?

  • AS is to specify an alias is not required in some banks serves only to highlight the abbreviation.

  • I tested the INNER JOIN and the result is blank. LEFT, Right only shows me one of the tables. Is there any other solution?

Show 2 more comments

1

To illustrate the use of JOIN as @perdeu falou, follows

<?php
include("conectar.php");

$quantidade = 1;
$pagina = (isset($_GET['pagina'])) ? (int)$_GET['pagina'] : 1;
$inicio = ($quantidade * $pagina)-$quantidade;  
$sql = "SELECT * FROM tb_trabalhador as t ".
        " INNER JOIN tb_equipamentos as e ON t.id = e.trabalhador_id "
        " INNER JOIN tb_detalhe_trabalhador as d ON t.id = d.tb_trabalhador_id order by id asc LIMIT $inicio, $quantidade";
$qr = mysql_query($sql) or die (mysql_error());
  while($exibe = mysql_fetch_array($qr)){

If the table tp_equipamento is not always mandatory, that is, it may not have related to tp_trabalhador, you will have to use the LEFT JOIN

  • does not need the Inner Join

  • only a question. After the "AS" the letters are corresponded to what?

0

Very simple way using the junction in the clause WHERE

<?php
include("conectar.php");

$quantidade = 1;
$pagina = (isset($_GET['pagina'])) ? (int)$_GET['pagina'] : 1;
$inicio = ($quantidade * $pagina)-$quantidade;  
$sql = "SELECT * FROM tb_trabalhador as t, tb_equipamentos e , tb_detalhe_trabalhador d ".
       " WHERE t.id = e.trabalhador_id AND t.id = d.tb_trabalhador_id ".
       " order by id asc LIMIT $inicio, $quantidade";
$qr = mysql_query($sql) or die (mysql_error());
  while($exibe = mysql_fetch_array($qr)){

  • @lost look here without the Inner Join

  • Okay, another way to do it.. However, you could post the reply instead of commenting on it.

  • 3

    This way of joining the tables was done in old databases (ansi-89 syntax) which uses the join is newer (ansi-92 syntax), I believe leave the WHERE Only for filters is more legible than using it to make junctions and filters.

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