php mysql error No database selected แก้ไขยังไงคะ

<?php

copy($_FILES["fileCSV"]["tmp_name"],$_FILES["fileCSV"]["name"]); // Copy/Upload CSV

$objConnect = mysql_connect("localhost","user","pass") or die("Error Connect to Database"); // Conect to MySQL
$objDB = mysql_select_db("test_check");

$strFileName = "test.txt";
$objFopen = fopen($strFileName, 'r');
if ($objFopen) {
    while (!feof($objFopen)) {
        $file = fgets($objFopen, 4096);
	$strSQL = "INSERT INTO detail";
	$strSQL .="(Name) ";
	$strSQL .="VALUES ";
	$strSQL .="('".$file."') ";
	$objQuery = mysql_query($strSQL);
        echo mysql_error();
    }
    fclose($objFopen);
}

echo "Import Done.";
?>