PHP Manual: dbx

Description

string dbx_error ( object link_identifier )

dbx_error() returns a string containing the error message from the last function call of the abstracted module (e.g. mysql module). If there are multiple connections in the same module, just the last error is given. If there are connections on different modules, the latest error is returned for the module specified by the link_identifier parameter.

Example 1. dbx_error() example

<?php
$link   = dbx_connect(DBX_MYSQL, "localhost", "db", "username", "password")
    or die("Could not connect");

$result = dbx_query($link, "select id from non_existing_table");
if ($result == 0) {
    echo dbx_error($link);
}
dbx_close($link);
?>

Note: Always refer to the module-specific documentation as well.
The error message for Microsoft SQL Server is actually the result of the mssql_get_last_message() function.
The error message for Oracle (oci8) is not implemented (yet).