Solved

Check if column exists in mysql table with php

Posted on 2012-04-10
6
2,303 Views
Last Modified: 2012-04-10
Hi Experts!

As in title, I need a php script checking if column exists in table.

Thanks for any help.
0
Comment
Question by:Zado
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 4
  • 2
6 Comments
 
LVL 35

Expert Comment

by:gr8gonzo
ID: 37828526
The "information_schema" table in MySQL is a special, internal table that holds all the information about the database structure. You can query it like this:

SELECT column_name FROM information_schema.columns WHERE table_name = 'my_table'

You can use that method / query to check for column existence.
0
 
LVL 8

Author Comment

by:Zado
ID: 37828623
Thanks gr8gonzo, I wrote this:
$checkcolumn = mysql_query("SELECT $column FROM information_schema.columns WHERE table_name = '$tablename'");
if (mysql_num_rows($checkcolumn)>0) {echo "column does not exists!";} else {echo "column exists!";}

Open in new window

but it doesn't work as expected, I keep trying...
0
 
LVL 8

Author Comment

by:Zado
ID: 37828685
Ok, got it, it's probably not the best to do it, but it works, if you know better way, please let me know:

$tablename = $_GET['table'];
		$column = "UserID";
		
		$columnlist = array();
		$checkcolumn = mysql_query("SELECT column_name FROM information_schema.columns WHERE table_name = '$tablename'");
		while ($row = mysql_fetch_array($checkcolumn)) {
			$columnlist[] = $row['column_name'];
		}
		$columnlist = implode(',',$columnlist);
		if (strpos($columnlist,$column)!==false) {echo "column exists!";} else {echo "column does not exists!";}

Open in new window

0
PeopleSoft Has Never Been Easier

PeopleSoft Adoption Made Smooth & Simple!

On-The-Job Training Is made Intuitive & Easy With WalkMe's On-Screen Guidance Tool.  Claim Your Free WalkMe Account Now

 
LVL 8

Author Comment

by:Zado
ID: 37828692
*up  'it's probably not the best way to do it'
0
 
LVL 35

Accepted Solution

by:
gr8gonzo earned 500 total points
ID: 37828697
Sorry, try this:

$checkcolumn = mysql_query("SELECT COLUMN_NAME FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME='{$tablename}' AND COLUMN_NAME = '{$column}';");
if (mysql_num_rows($checkcolumn)>0) {echo "column does not exists!";} else {echo "column exists!";}

Open in new window

0
 
LVL 8

Author Closing Comment

by:Zado
ID: 37828829
Thanks :-)
0

Featured Post

Don't Cry: How Liquid Web is Ensuring Security

WannaCry is just the start. Read how Liquid Web is protecting itself and its customers against new threats.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Creating and Managing Databases with phpMyAdmin in cPanel.
Nothing in an HTTP request can be trusted, including HTTP headers and form data.  A form token is a tool that can be used to guard against request forgeries (CSRF).  This article shows an improved approach to form tokens, making it more difficult to…
The viewer will learn how to dynamically set the form action using jQuery.
The viewer will learn how to look for a specific file type in a local or remote server directory using PHP.

690 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question