Feature Description

In Postgres, STORED columns aren't updatable, but need to be read from db.

Is your feature request related to a problem? Please describe.

eg

    total_amount NUMERIC(12, 2) NOT NULL GENERATED ALWAYS AS (amount * quantity) STORED,

gives
ERROR unhandledRejection column "total_amount" can only be updated to DEFAULT

Describe the solution you'd like

A new readOnly option in model, or a VIRTUAL/GENERATED column type (see comments)

        total_amount: {
        	type: DataTypes.DOUBLE,
        	readOnly: true
        },

This should be easy to implement. Here
https://github.com/sequelize/sequelize/blob/042cd693635ffba83ff7a2079974692af6f710a7/src/dialects/abstract/index.js
add

/* features specific to readOnly values */
  readOnly: {
    /* does the dialect require modification of insert queries when inserting */
    identityInsert: false,

    /* does the dialect support inserting default/null values */
    defaultValue: false,

    /* does the dialect support updating fields */
    update: false
  },

Why should this be in Sequelize

In databases, some fields are read-only. eg Postgres STORED columns. This might also be used for views in future.

Describe alternatives/workarounds you've considered

Using autoIncrement, but that doesn't work properly and it's not autoIncrement, it's a read-only column.

Feature Request Checklist

Is this feature dialect-specific?

• No. This issue is relevant to Sequelize as a whole.
• Yes. This issue only applies to the following dialect(s): XXX, YYY, ZZZ

Would you be willing to implement this feature by submitting a Pull Request?

• Yes, I have the time and I know how to start.
• Yes, I have the time but I don't know how to start, I would need guidance.
• No, I don't have the time, although I believe I could do it if I had the time...
• No, I don't have the time and I wouldn't even know how to start.