mysqli_error
    (PHP 5)
mysqli_error -- Returns a string description of the last error
Description
Procedural style:
string 
mysqli_error ( object link)
Object oriented style (property)
class 
mysqli { 
string error
}
     The mysqli_error() function is identical to the corresponding
     mysqli_errno() function in every way, except instead of returning
     an integer error code the mysqli_error() function will return
     a string representation of the last error to occur for the database connection 
     represented by the link parameter. If no error has occured,
     this function will return an empty string.
    
Return values
      A string that describes the error. An empty string if no error occurred. 
    
Example
Example 1. Object oriented style 
<?php $mysqli = new mysqli("localhost", "my_user", "my_password", "world");
  /* check connection */ if (mysqli_connect_errno()) {     printf("Connect failed: %s\n", mysqli_connect_error());     exit(); }
  if (!$mysqli->query("SET a=1")) {     printf("Errormessage: %s\n", $mysqli->error); }
  /* close connection */ $mysqli->close(); ?>
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Example 2. Procedural style 
<?php $link = mysqli_connect("localhost", "my_user", "my_password", "world");
  /* check connection */ if (mysqli_connect_errno()) {     printf("Connect failed: %s\n", mysqli_connect_error());     exit(); }
  if (!mysqli_query($link, "SET a=1")) {     printf("Errormessage: %s\n", mysqli_error($link)); }
  /* close connection */ mysqli_close($link); ?>
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     The above examples would produce the following output:
    
Errormessage: Unknown system variable 'a'  |