SQLSTATE[HY000]: General error: trying to execute an empty query

This error is typically caused by using an empty query string or statement when executing a PDO query or prepared statement. This can occur in any of the following scenarios within PHP code:

1. The query string or statement is empty.

Please ensure that your query string or SQL statement contains a valid SQL query. If the string or statement is empty, this error will be thrown. You can use `var_dump()` or an `echo` statement to print the query string or statement before executing the query, to verify that they are correctly set.

2. Query parameter is empty

This error can also occur when using a PDO statement with bound parameters but without providing any parameters. Please ensure that the bound parameters are assigned values before executing the statement.

Here is an example of a PDO query that uses bound parameters:

$stmt = $pdo->prepare("SELECT * FROM users WHERE username = :username");
$username = "JohnDoe";
$stmt->bindParam(":username", $username);
$stmt->execute();

Please note that the $username variable contains the value of the bound parameter, even if it is merely a single string value.

If you still encounter this error, it is recommended that you check whether your SQL query and parameters are correctly configured, as well as whether there are any other syntax errors.