Updating a values in mysql
I have tried this example but the SQL in the selected answer does not execute because My SQL Workbench doesn't seem to like the FROM in the UPDATE.
My problem is how do i update the values of user roles on the 3rd table.
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If you update a column that has been declared , an error occurs if strict SQL mode is enabled; otherwise, the column is set to the implicit default value for the column data type and the warning count is incremented.The data type used for the result of a calculation on numeric operands depends on the types of the operands and the operations performed on them.For more information, see Section 12.6.1, “Arithmetic Operators”.If I assign a user_id 34 to admin(role_id = 2) user_id 34 to supervisor(role_id = 3) I should have two entries on Role_User table.
Now I would like to update user_id 34 to admin(role_id = 1) How do I do this on rails I have updating the user details with @user = User.where(id: user_params[:id]); @user.update_all( first_name: user_params[:first_name], last_name: user_params[:last_name], email: user_params[:email], contact_number: user_params[:contact_number], user_name: user_params[:user_name], password: user_params[:password] ); If you set up a many_to_many connection through rails, like below for example, then you don't have to touch the relational table.I am finding it difficult to update the information which is edited to the database , as I want the student to remain on the same page.