Troubleshooting "Field 'id' Doesn't Have a Default Value" Error
When creating a database table, it's crucial to address the absence of a default value for primary key fields. This error can arise as you are creating a table named card_games.
The error message "Field 'id' doesn't have a default value" indicates that the id column, which serves as the primary key for identifying unique rows in the table, lacks a predetermined value.
To rectify this, modify your table definition to ensure that the id column is auto-incremented. This enables the database to automatically assign unique values to each new row, obviating the need to explicitly specify the id value during data insertion.
Here's the updated table definition:
CREATE TABLE card_games ( id int(11) NOT NULL AUTO_INCREMENT, nafnleiks varchar(50), leiklysing varchar(3000), prentadi varchar(1500), notkunarheimildir varchar(1000), upplysingar varchar(1000), ymislegt varchar(500), PRIMARY KEY (id) );
With this modification, you can now insert new rows without explicitly specifying the id value:
insert into card_games (nafnleiks, leiklysing, prentadi, notkunarheimildir, upplysingar, ymislegt) values('Svartipétur', 'Leiklýsingu vantar', 'Er prentað í: Þórarinn Guðmundsson (2010). Spilabókin - Allir helstu spilaleikir og spil.', 'Heimildir um notkun: Árni Sigurðsson (1951). Hátíðir og skemmtanir fyrir hundrað árum', 'Aðrar upplýsingar', 'ekkert hér sem stendur' );
Alternatively, you can manually assign values to the id field, ensuring uniqueness to prevent duplicate rows:
insert into card_games (id, nafnleiks, leiklysing, prentadi, notkunarheimildir, upplysingar, ymislegt) values(1, 'Svartipétur', 'Leiklýsingu vantar', 'Er prentað í: Þórarinn Guðmundsson (2010). Spilabókin - Allir helstu spilaleikir og spil.', 'Heimildir um notkun: Árni Sigurðsson (1951). Hátíðir og skemmtanir fyrir hundrað árum', 'Aðrar upplýsingar', 'ekkert hér sem stendur' );
By addressing the missing default value for the primary key field, you can successfully create and populate the card_games table, ensuring data integrity and preventing duplicate rows.
The above is the detailed content of How to Fix \'Field \'id\' Doesn\'t Have a Default Value\' Error in MySQL?. For more information, please follow other related articles on the PHP Chinese website!

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