![]() The majority, if not all, of the examples provided, is performed on a personal development/learning workstation-environment and should not be considered production quality or ready. They are not the utmost best solution(s). Among those, he shares a love of tabletop RPG games, reading fantasy novels, and spending time with his wife and two daughters.ĭisclaimer: The examples presented in this post are hypothetical ideas of how to achieve similar types of results. Other favorite activities find him with his nose buried in a good book, article, or the Linux command line. Josh Otwell has a passion to study and grow as a SQL Developer and blogger. To receive email notifications (Never Spam) from this blog (“Digital Owl’s Prose”) for the latest blog posts as they are published, please subscribe (of your own volition) by clicking the ‘Click To Subscribe!’ button in the sidebar on the homepage! (Feel free at any time to review the Digital Owl’s Prose Privacy Policy Page for any questions you may have about: email updates, opt-in, opt-out, contact forms, etc…)īe sure and visit the “Best Of” page for a collection of my best blog posts. Visit the Portfolio-Projects page to see blog post/technical writing I have completed for clients. Please share your findings here, with someone else you know who would get the same value out of it as well. I truly hope you discovered something interesting and enlightening. Thank you for taking the time to read this post. ![]() Like what you have read? See anything incorrect? Please comment below and thanks for reading!!! A Call To Action! MySQL CREATE TABLE in PHPMyAdmin – with examples.Import CSV file data into MySQL table with phpMyAdmin ( one of my most read articles on Medium to date!).Export MySQL data to CSV with phpMyAdmin.Use phpMyAdmin to change column name and datatype in MySQL.Visit these other blog posts I have written about basic phpMyAdmin usage: Notice both the ‘first_name’ and ‘last_name’ columns have a silver key icon for their respective rows, indicating they have the UNIQUE constraint INDEX in place. Table users definition with Unique constraint for columns first_name and last_name If you specify a prefix value for a column in a UNIQUE index, the column values must be unique within the prefix length.” Table Structureįor the examples in this post, we have this ‘users’ table with 3 columns: ‘user_id’, ‘first_name’, and ‘last_name’: For all engines, a UNIQUE index permits multiple NULL values for columns that can contain NULL. An error occurs if you try to add a new row with a key value that matches an existing row. ![]() “A UNIQUE index creates a constraint such that all values in the index must be distinct. ![]() Below is the exact verbiage directly from the official on-line MySQL CREATE TABLE section: In more correct terms, UNIQUE is actually an INDEX. Every value must be different in some way. In other words, no duplicates can exist in a column that is created with the UNIQUE constraint. The UNIQUE constraint ensures that a column’s values remain unique or individual among all the other values in the column. Since coffee is my favorite drink, you can even buy me one if you would like! If you enjoy the content written here, by all means, share this blog and your favorite post(s) with others who may benefit from or like it as well.
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