How are multiple Wordpress WPDB queries handled?

Question

In my code, I use this query to get all the rows where credited field is false:

$uncredited_incentives_query = $wpdb->prepare(
    "SELECT * FROM $incentives_table WHERE user_id = %s AND credited = FALSE ",
    $sponsor->ID
);

Then I work with the results. Then I have to set the credited field as true for the rows which were returned by the previous query. I am currently using this aproach.

$wpdb->update(
$incentives_table,
array(
    'credited' => true
),
array(
    'user_id'  => $sponsor->ID,
    'credited' => false
)
);

But I don't want to include any new rows which may have been added since this code was executed. So I want to know how is that possible? Am I using the correct approach?. If not, then how can I do so?

Thanks in advanced.

Answer 1

Method 1 - Check for the last row id.

SELECT * FROM $incentives_table WHERE user_id = %s AND credited = FALSE

You can get the last row in the array and get the column row_id.

And then you can update with the where

WHERE user_id = %s AND credited = FALSE AND row_id <= {last row id}

Method 2 - temp column.

First you need to create another column in the table for this lets call it for example 'temp_user_update`.

Now when you want to get the data and then update you need first to create variable to use in your code and save it in this column.

$temp_user_update = $sponser->ID.time();

UPDATE table set temp_user_update='{$temp_user_update}' WHERE user_id = %s AND credited = FALSE

After this step you can select and update with the WHERE temp_user_update='{$temp_user_update}'