Resolving MySQL Error 1121: Correcting NULL Columns in Indexes
If you’re working with MySQL and encounter Error 1121 – SQLSTATE: 42000 (ER_NULL_COLUMN_IN_INDEX) Column ‘%s’ is used with UNIQUE or INDEX but is not defined as NOT NULL, it means that there is a column included in an index or unique constraint that allows NULL values. In MySQL, a column that is part of a …