You need a primary key for every database table, and I think that is the primary index too. Indexes are used to speed up queries, and you should have an index of the column if you used it in the WHERE-part of an SQL-queries for performance reasons.
Using TEXT in cases where you don´t need it is bad. It is better to limit you users for some fields i.e. title and url, since you have an index on url. And I don't think you can use index on columns that are of type TEXT. I don´t think a FULLTEXT-index on url is what you want.
I would recommend you to read up about databases in an introductory text or website.
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You need a primary key for every database table, and I think that is the primary index too. Indexes are used to speed up queries, and you should have an index of the column if you used it in the
WHERE-part of an SQL-queries for performance reasons.Using
TEXTin cases where you don´t need it is bad. It is better to limit you users for some fields i.e. title and url, since you have an index on url. And I don't think you can use index on columns that are of typeTEXT. I don´t think aFULLTEXT-index on url is what you want.I would recommend you to read up about databases in an introductory text or website.