问题
for learning purposes, why does php cries about the following code and gives the following warning:
Warning: mysqli_stmt::close() [mysqli-stmt.close]: invalid object or resource mysqli_stmt in C:\public_html\admin\disctrack.php on line 14
12 $conn = connect('w'); // connect to a database in write mode
13 $stmt = $conn->stmt_init(); // initialize a prepared statement
14 $stmt->close(); // close statement
回答1:
From the mysqli::stmt_init documentation:
Any subsequent calls to any mysqli_stmt function will fail until mysqli_stmt_prepare() was called.
来源：https://stackoverflow.com/questions/7297640/warning-mysqli-stmtclose-mysqli-stmt-close-invalid-object-or-resource-my