Query search for value in Database

Question

I want to show the results obtained in a form but when saving in the comic null but kept so:

Date: 0000-00-00 And Numero: 0

Query have so:

$sql = mysql_query ("Select *, Count(*) from tabela1, tabela2 where campo1 = 0 and campo2= '0000-00-00' and campo3 is Null and campo4......'")

But he’s not showing me the result. I have something wrong with the code?

Answer 1

In your question, you are indicating that the difficulty is in the operation of inserting new lines in the database. After that, you have a query to collect results and you indicate that the query is not working as intended, let’s analyze:

• How to create the table so that things work as you want;
• Perform data insertion;
• Collect existing records.

Create the table

How do you intend the columns with the name campo1 and campo2 are null by default, you have to give this indication in the table itself:

As you can see, we are indicating that the default value for the column campo1 and campo2 is null.

The code for creating the table would be:

CREATE TABLE IF NOT EXISTS `tabela1` (
  `id` int(13) NOT NULL AUTO_INCREMENT,
  `campo1` int(13) DEFAULT NULL,
  `campo2` date DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=MyISAM  DEFAULT CHARSET=utf8 AUTO_INCREMENT=1;

Insert results

With the table properly prepared to accept null in the columns campo1 and campo2, the insertion consultation would be:

INSERT INTO `tabela1` ( `id` , `campo1` , `campo2` )
VALUES (NULL , NULL , NULL);

This will insert a type row into the table:

Hold consultations

Now that the table is in the desired form, the queries looking for records null can already be realized.

Same query as in the question, that is, the column campo1 equal to 0 and the column campo2 equal to null or equal to 0000-00-00:

SELECT *
FROM `tabela1`
WHERE `campo1` =0
AND (
`campo2` IS NULL
OR `campo2` = '0000-00-00'
)

That returns us precisely two records where both are with the value in the column campo1 equal to 0 and the value of the column campo2 equal to NULL in ID 1 and equal to 0000-00-00 in ID 3:

Answer 2

I figured it out. Although it appears in the database 0000-00-00 on the date I put like this: I thank those who helped me :)

include("conectar.php");
$sql = mysql_query("SELECT * FROM tb_trabalhador WHERE AlvaraNumero = 0 
 AND(AlvaraValidade='' or AlvaraValidade is Null or AlvaraValidade='0000-00-00')
 AND (AlvaraAnexo='' or AlvaraAnexo is Null)
 AND AcidenteNumero = 0
 AND (AcidenteValidade='' or AcidenteValidade is Null or AcidenteValidade='0000-00-00')    
 AND (AcidenteAnexo='' or AcidenteAnexo is Null)
 AND SeguroNumero = 0
 AND (SeguroValidade='' or SeguroValidade is Null or SeguroValidade='0000-00-00' )
 AND (SeguroAnexo='' or SeguroAnexo is Null)
 AND InstaladorNumero = 0
 AND (InstaladorValidade='' or InstaladorValidade is Null or InstaladorValidade='0000-00-00')
 AND (InstaladorAnexo='' or InstaladorAnexo is Null) " ) or DIE( mysql_error());

 while($exibe = mysql_fetch_array($sql)){ 

Answer 3

Name the tables to show in which table the field you pass by "WHERE".

Ex:

$sql = mysql_query ("SELECT *, COUNT(*) FROM tabela1 AS tbl1, tabela2 AS tbl2 WHERE tbl1.campo1 = 0 and tbl2.campo2= '0000-00-00' and tbl1.campo3 is Null and tbl2.campo4......'");