php – How do I test if my MySQL update query was successful in CodeIgniter?-ThrowExceptions

Exception or error:

I have a model function that updates a user in my CodeIgniter application:

// updates first of a user, return true if successful, false if not.
public function updateFirstName($userId, $newFirstName) {
    $this->db->query("UPDATE users SET firstName='$newFirstName' WHERE id=$userId");
    return // whether request was successful?
}

How do I return a boolean value that ensures the user of ID $userId has been updated? For instance, it should return false if no user was found with ID $userId.

How to solve:

As commented, have you tried $this->db->affected_rows()?

That will tell you how many rows were updated.

Answer:

if ($this->db->affected_rows() > 0)
{
  return TRUE;
}
else
{
  return FALSE;
}

or

if ($this->db->affected_rows() > 0)
  return TRUE;
else
  return FALSE;

or

return ($this->db->affected_rows() > 0) ? TRUE : FALSE; 

EDIT

also(much better)

return ($this->db->affected_rows() > 0);

Answer:

Check this for more information. Active Records

public function updateFirstName($userId, $newFirstName) {

   return $this->db
               ->where('id', $userId)
               ->update("users", array('firstName' => $newFirstName));
}

With this way you will also avoid sql injection that you had before

Answer:

A better solution I’ve found is to manage the difference between an ERROR and 0 affected rows. 0 affected rows is not necessarily a bad thing, but an error is something you do want to know about:

if ($this->db->_error_message()) {
    return FALSE; // Or do whatever you gotta do here to raise an error
} else {
    return $this->db->affected_rows();
}

Now your function can differentiate…

if ($result === FALSE) {
    $this->errors[] = 'ERROR: Did not update, some error occurred.';
} else if ($result == 0) {
    $this->oks[] = 'No error, but no rows were updated.';
} else {
    $this->oks[] = 'Updated the rows.';
}

Just some quick hacking there – you should obviously make the code far more verbose if you have other people using it.

The point is, consider using _error_message to differentiate between 0 updated rows and a real problem.

Answer:

You can use $this->db->affected_rows() in Codeigniter this returns a numeric value when doing “write” type queries (insert, update, etc.).

In MySQL DELETE FROM TABLE returns 0 affected rows. The database class has a small hack that allows it to return the correct number of affected rows. By default this hack is enabled but it can be turned off in the database driver file. (From CI user guide). For deleted row in Ci it returns 1.

Answer:

You may use $this->db->affected_rows(); to check whether query runs successfully or not

Answer:

I have use this code for checking update query.

$status = $this->db->query("UPDATE users SET firstName='$newFirstName' WHERE id=$userId"); 
if($status)
   return true;
else
    return false;

Answer:

Use a stored procedure, you can check the result.

Below is a stored procedure example :

CREATE DEFINER=`root`@`localhost` PROCEDURE `usp_UpdateInfo`(tableId int,tableName varchar(100) charset utf8,description varchar(400) charset utf8)

BEGIN

    declare exit handler for sqlexception select 0 as `result`;

    update table
    set `name` = tableName,
        description = description
    where id = tableId;
    select 1 as `result` ;
END

PHP example code :

$this->load->database();

$rs = $this->db->query('call usp_UpdateInfo(?,?,?)',array($tableId,$tableName,$description));
$this->db->close();     
return $rs->result_array();

Answer:

public function updateInfo($newinfo) {
    $this->db->update("some_table", $newinfo);
    return ($this->db->affected_rows() > 0);
}

This will either return true or false

Answer:

Try this:

public function updateFirstName($userId, $newFirstName) {
    $this->db->where('id', $userId);
    $this->db->set('firstName', $newFirstName);
    $sql = $this->db->update('users');

    if ($sql) { return TRUE; }  // $sql - boolean true or false
}

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