diff --git a/adminer/include/functions.inc.php b/adminer/include/functions.inc.php
index 998e0c28..9d909019 100644
--- a/adminer/include/functions.inc.php
+++ b/adminer/include/functions.inc.php
@@ -151,6 +151,11 @@ function get_file($key) {
 	return (!$_FILES[$key] || $_FILES[$key]["error"] ? $_FILES[$key]["error"] : file_get_contents($_FILES[$key]["tmp_name"]));
 }
 
+function upload_error($error) {
+	$max_size = ($error == UPLOAD_ERR_INI_SIZE ? ini_get("upload_max_filesize") : null); // post_max_size is checked in index.php
+	return lang('Unable to upload a file.') . ($max_size ? " " . lang('Maximum allowed file size is %sB.', $max_size) : "");
+}
+
 function odd($s = ' class="odd"') {
 	static $i = 0;
 	if (!$s) { // reset counter
diff --git a/adminer/lang/cs.inc.php b/adminer/lang/cs.inc.php
index 475cf8b5..ecb999c6 100644
--- a/adminer/lang/cs.inc.php
+++ b/adminer/lang/cs.inc.php
@@ -228,4 +228,5 @@ $translations = array(
 	'Binary' => 'Binární',
 	'Lists' => 'Seznamy',
 	'Relations' => 'Vztahy',
+	'Maximum allowed file size is %sB.' => 'Maximální povolená velikost souboru je %sB.',
 );
diff --git a/adminer/select.inc.php b/adminer/select.inc.php
index 337d1ba9..93a1196a 100644
--- a/adminer/select.inc.php
+++ b/adminer/select.inc.php
@@ -166,7 +166,7 @@ if ($_POST && !$error) {
 		$result = queries("INSERT INTO " . idf_escape($_GET["select"]) . "$cols VALUES" . implode(",", $rows));
 		query_redirect(queries(), remove_from_uri("page"), lang('%d row(s) has been imported.', $dbh->affected_rows), $result, false, !$result);
 	} else {
-		$error = lang('Unable to upload a file.');
+		$error = upload_error($file);
 	}
 }
 
diff --git a/adminer/sql.inc.php b/adminer/sql.inc.php
index e1c2a6e8..8f9d2488 100644
--- a/adminer/sql.inc.php
+++ b/adminer/sql.inc.php
@@ -3,7 +3,8 @@ page_header(lang('SQL command'), $error);
 $history = &$_SESSION["history"][$_GET["server"]][$_GET["db"]];
 
 if (!$error && $_POST) {
-	if (is_string($query = (isset($_POST["file"]) ? get_file("sql_file") : $_POST["query"]))) { // get_file() returns error as number
+	$query = (isset($_POST["file"]) ? get_file("sql_file") : $_POST["query"]);
+	if (is_string($query)) { // get_file() returns error as number
 		@set_time_limit(0); // set_time_limit() can be disabled
 		$query = str_replace("\r", "", $query); // parser looks for \n
 		$query = rtrim($query);
@@ -64,7 +65,7 @@ if (!$error && $_POST) {
 			echo "<p class='message'>" . lang('No commands to execute.') . "\n";
 		}
 	} else {
-		echo "<p class='error'>" . lang('Unable to upload a file.') . "\n";
+		echo "<p class='error'>" . upload_error($query) . "\n";
 	}
 }
 ?>