Update a specific column in sql

Question

How to get updated a single column by giving the input.Here is my code.

$sql="UPDATE isourcetest SET hostname='".$_POST['fname']."', 
IP='".$_POST['Iname']."', location='".$_POST['Lname']."', 
network='".$_POST['nname']."', OSversion='".$_POST['oname']."', 
RAM='".$_POST['rname']."',CPUcore='".$_POST['cname']."',
CPUspeed='".$_POST['cpname']."', 
Hardwaremodel='".$_POST['hname']."'
WHERE hostname='".$_POST['fname']."'";

But here if i try to update a column the entire row will be updated. Please suggest a solution.I am new in sql.

Either build the query dynamically, based upon the input. Or make sure that all the input is included (including data identical to that being updated). — Strawberry, Sep 06 '16 at 10:21
***NEVER*** put user / POST / GET data directly into a SQL query like this. Read up on `Escaping SQL inputs` and `Prepared Statements` . — Martin, Sep 15 '16 at 09:19

score 1 · Answer 1 · answered Sep 06 '16 at 08:51

1

You only need to write an update of one column, for example of hostname:

$sql="UPDATE isourcetest SET hostname='".$_POST['fname']."' 
WHERE hostname='".$_POST['fname']."'";

answered Sep 06 '16 at 08:51

Tedo G.

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3
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1

Yes,but i want to update not only host name but also other fields with respect to the input giving through the portal. – abhi Sep 06 '16 at 08:57
Your question title does not really says that :) – Tedo G. Sep 06 '16 at 08:59

score 0 · Answer 2 · edited May 23 '17 at 10:29

0

Use COALESCE()

$sql="UPDATE isourcetest SET hostname=COALESCE('".$_POST['fname']."', hostname), 
IP=COALESCE('".$_POST['Iname']."', IP),.....etc

WHERE hostname='".$_POST['fname']."'";

Let me know if it works

edited May 23 '17 at 10:29

Community

1
1

answered Sep 06 '16 at 09:14

Rohit Dhiman

2,691
18
33

score 0 · Answer 3 · answered Sep 06 '16 at 09:42

0

try this..

$sql="UPDATE isourcetest SET ";
if($_POST['fname'] != '')
$sql."hostname='".$_POST['fname']."',"; 
.
.
if($_POST['hname'] != '')
$sql."Hardwaremodel='".$_POST['hname']."',";

rtrim($sql,',');

$sql."WHERE hostname='".$_POST['fname']."'";

answered Sep 06 '16 at 09:42

Vishal Gupta

124
6

score 0 · Answer 4 · edited Sep 15 '16 at 09:20

0

Below code worked for me.

if($_POST['fname'])
{
$sql="UPDATE tablename SET hostname='".$_POST['fname']."' WHERE hostname='".$_POST['fname']."'";
if (!mysql_query($sql,$db))
  {
  die('Error: ' . mysql_error());
  }

}
.
.
.
if($_POST['hname'])
{
$sql="UPDATE tablename SET Hardwaremodel='".$_POST['hname']."' WHERE hostname='".$_POST['fname']."'";
if (!mysql_query($sql,$db))
  {
  die('Error: ' . mysql_error());
  }

}

Thank you all for the support.

edited Sep 15 '16 at 09:20

Martin

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answered Sep 15 '16 at 09:10

abhi

55
1
1
6

Stop using MySQL_ as soon as possible and research using `MySQLi_` and or `PDO`. MySQL_ is flawed, unsafe, and Deprecated. Also do not insert POSTed or GET data directly into SQL queries as you can't trust it. – Martin Sep 15 '16 at 09:21

Update a specific column in sql

4 Answers4