MySQL Managed Database can't modify database without setting primary key, but I can't set primary key without modifying the database.

Hi, so I currently have a table with the following datatypes: column1 -> TEXT column2 -> TEXT column3 -> TEXT

This table is huge, with over 500k+ rows. When I initially started using MySQL on DO, I hardly knew what a primary key was, so I never set one up.

However, I’ve encountered a loop of a problem: In order to set a primary key, I must have a column in the database which has a specific amount of characters, e.g. VARCHAR(10). If I don’t have it, I will get something similar to this:

Error: BLOB/TEXT column 'columnName' used in key specification without a key length

However, in order to even set my column to have a specific key length, I have to modify the table.

As a result, I try to modify the table, using something on the lines of MODIFY TABLE tableName ALTER COLUMN columnName VARCHAR(length). Which tells me that:

Error: Unable to create or change a table without a primary key, when the system variable 'sql_require_primary_key' is set. Add a primary key to the table or unset this variable to avoid this message. Note that tables without a primary key can cause performance problems in row-based replication, so please consult your DBA before changing this setting.

Which creates an infinite loop of me not even being able to set a primary key in the first place.

Now I’ve took a look about the possibility of perhaps setting the system variable sql_require_primary_key. However after taking a look at stackoverflow I’ve been suggested it’s not possible to do so.

Can someone help me in this? Thank you.