Preventing Multiple Insertions on Form Submission in PHP
Challenge:
In some instances, users may unintentionally press the "Enter" key multiple times, leading to duplicate posts or insertions.
Alternative Solution:
Aside from checking for duplicate posts based on title and content, several additional approaches can effectively prevent this issue:
-
Disable Submit Button via JavaScript:
This method involves disabling the form's submission button once it has been clicked. However, it's not foolproof as users may still submit forms through other means, and those with JavaScript disabled will be affected.
-
Session-based Timestamp:
PHP sessions can be utilized to set a timestamp when a post is received. Upon subsequent submissions, the time difference between the current timestamp and the stored timestamp can be checked. If the difference is within a predefined limit (e.g., 2 seconds), the submission can be flagged as a duplicate.
-
Unique Token:
Generation of a unique token for each POST request ensures that the submitted form has not been previously sent. A token value is stored in session and included in the form's submission. Any mismatch between the submitted token and the session token indicates a double submission attempt, which can be rejected accordingly.
These alternatives offer robust solutions to prevent multiple insertions on form submissions, ensuring data integrity and reducing the likelihood of duplicate records.
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