How to retrieve data from 2 column in one table? - sql

Question

I have a table named accessories_other in my database. In the table, I have column :
1) Item
2)Available
This is the illustration on how the data in the respective column.
Item
Mouse
Keyboard
Cable
Available
4
6
3
The thing is, I would like to select Item = 'Mouse' together with column 'Available'=4. If the available mouse is less than 5, it will send me an email for the next step. But I stuck until this stage.
This is SQL statement that I create, and it count each row for 'Available' column, and send the email if the row of Available column is less than 5, which is not I want.
$sql ="SELECT Item, Available FROM accessories_other WHERE Item ='Mouse'
AND Available <5";
How do I do so that it can retrieve mouse which is the availability less than 5.

Answer 1

This is just to show how it could be done . You should be using MySQLi
or PDO . Also if in Production environment , you should not be
displaying MySQL errors to the user .
You could do it either way :
// SQL to find Available value for Item Mouse
$sql = "SELECT Item, Available FROM accessories_other
WHERE Item = 'Mouse'";
$result = mysql_query( $sql ) or die( 'Query failed.'.mysql_error() );
$row = mysql_fetch_array( $result ) ;
if( mysql_num_rows( $result ) > 0 )
{
echo $row['Item'] ,': ' ,$row['Available'];
if( $row['Available'] < 5 )
{
// Code to send email
}
else
{
// Code to what ever you would like to do here
}
}
or
// SQL to find Available value for Item Mouse if it is less than 5
$sql = "SELECT Item, Available FROM accessories_other
WHERE Item = 'Mouse' AND Available < 5";
$result = mysql_query( $sql ) or die( 'Query failed.'.mysql_error() );
if( mysql_num_rows( $result ) > 0 )
{
// Code to what ever you would like to do here
}
else
{
echo $row['Item'] ,': ' ,$row['Available'];
// Code to send email
}

Answer 2

I think your query will not show results of mouse which is lesser than 5..
I suggest you try:
$sql ="SELECT Item, Available FROM accessories_other WHERE Item ='Mouse';
and then, try to implement your code in another language..
if I'm not mistaken, you're using php..

Answer 3

your query should return exactly one row if you have data in table "accessories" as shown here. unless you have duplicates like multiple rows rows with Item = 'Mouse' and same or different value which is also less than 5 then only query will return multiple results.
also just notice that in the explanation you use the table "accessories" but in sample query you have used table "accessories_other". make sure you are working against the right table.