I think I found the most semantic solution: If I want to relate a given row of data to “nowhere”, NULL is the best value to reflect that. And it even works with constraints on the field!
Related Posts:
- Plugin: database creation
- WordPress how do I echo SUM from a column of a MySQL table by user id AND type_operation
- Can I log the searches that are returning 404 in the DB?
- Objective Best Practices for Plugin Development? [closed]
- Post meta vs separate database tables
- How do i best handle custom plugin page actions?
- How to create an API for my plugin?
- Is it ever okay to include inline CSS in plugins?
- Plugins in symlinked directories?
- Is it mandatory to use $wpdb->prefix in custom tables
- In Which Contexts are Plugins Responsible for Data Validation/Sanitization?
- Plugin Form Submission Best Practice
- Update Option Stored in Multi-Dimensional Array
- Best way to abort plugin in case of insufficient PHP version?
- How can I configure Docker for developing and deploying a custom theme?
- What do you think about custom designed plugin/theme options UIs?
- No Error Log File, no debug info
- Where to put third party PHP library?
- Is the new WordPress 3.1 admin bar pluggable and how can I extend it?
- How to use PanelColorSettings in custom Gutenberg block?
- Getting a peer review for my new plugin?
- Default table collation on plugin activation?
- Optimize shortcode callbacks
- Using a database view = evil incarnate?
- How to integrate a PHP webmail script into the backend of WordPress?
- Using filters and actions for plugin API?
- Is There A Hook To Process The Content Of The Text Widget?
- How to Change the Entire WordPress Admin panel Look and Feel?
- Writing a plugin that notify my friends of new post that mentions(@) them
- Getting wrong relationship value in $args in wp_Query?
- WordPress and multithreading
- Is using custom table to suit business needs instead of transients a big hit to page load speed?
- Plugin Development for registered users
- Search: how to extend the existing search to include a custom table
- Is there documentation reference for forms in menu and setting pages?
- Optimising a big WordPress site
- wpdb->prepare and mysql UPDATE – how is it done?
- Enqueue script globally
- dbDelta SQL Query Not Working
- How to modify files inside wp-includes directory in wordpress
- How should I go about registering JavaScript that isn’t a file? [duplicate]
- dbDelta not installing database
- Is it necessary to do validation again when retrieving data from database?
- Custom entity search and display
- How to set a cookie for logged in users to md5($user->ID . “my_secret”)?
- What is the best way to store a few fields?
- Loading Modernizr (or other JavaScript libraries) for use in a plugin
- Adding columns to core tables
- How to query custom db table?
- Delete data from database using row action
- Show dynamic list of products from custom api of another database under same host
- How do I have now a duplicated user entry if this is not allowed (and I cannot replicate it)?
- Show message from backend
- Alternative functions for mysql_free_result and mysql_ping in wordpress functions
- how to get the post id in plugin
- Why in this archive page that call query_posts() function show only the last 10 posts?
- Make Database query only when option is updated
- Create Widget or Enable Shortcodes in Sidebar
- Can we intercept user_login and user_pass from a wp_login_form?
- How best to handle database version dependence (from $wp_db_version)
- WP: Search and replace in DB programmatically
- Using AND and bracket grouping in SQL not working
- Logout after clicking URL link results in “headers already sent” error
- Two different wordpress sites – same server and IP address. Gaining Access to database 1 of 2
- how to save wp_editor html content in options table
- Converting core modification to a plugin
- Comment “like” problem – “users who like this” avatar linking to current user profile instead of “liker’s” profile
- Plugin Development: Storing and Manipulating Data That Fits JSON in Database
- How to use a WP_Customize_Control outside of the Customizer?
- What might be the reason of Couldn’t fetch mysqli_result on another domain?
- How do I debug an error that a plugin is causing?
- How to replace settings in WordPress plugin from a theme
- Save temporary registration data
- How to remove/replace current page template?
- Update plugin settings option_name for big plugin update
- $wpdb->update Issue
- Integrating Custom Database with WordPress
- dbdelta failing with error: “WordPress database error Table ‘wp_2_myPlugin’ already exists
- Setting a post’s category
- Setting post_id for single.php based on URL without a redirect
- WordPress database error: [Query was empty] – using $wpdb->prepare()
- Extract Information from post content (using regex?)
- How to determine which capability to use?
- Serial Number from custom table not appear in woocommerce_email_before_order_table action
- Customise Grouped Product display in Woocommerce with custom column
- Custom Endpoint – Does it possible to use PUT method with WP API Rest?
- Why won’t this submenu page show? – My First WordPress Plugin
- Error code when migrate
- How to create a custom post-new.php page for plugin , no wp menu
- Want to know how to reveal a WordPress theme, considering the theme name is hidden?
- Why User_login key doesn’t work with wp_update_user()
- How to get inserted row IDs for bulk/batch insert with wpdb query?
- Save meta box data from selected dropdown list in bbpress reply form
- Metabox types list
- Where to save Gutenberg plugin data?
- Rate limiting ajax requests in WordPress
- WordPress Fatal error: Uncaught Error: Call to undefined function dbDelta()
- Does hooking into a plugin action / filter override the plugin’s function for that hook?
- How to prevent users from deleting their accounts?
- Hiding class namespace from plugin’s extensions