-- Migration 027: drop banner_path column from theses table.
-- Banners were merged into covers in migration 016; the column has been
-- vestigial since.  This is safe to run even if the column is already absent.
-- Safe to re-run: IF EXISTS makes it idempotent.

-- SQLite does not support DROP COLUMN directly in older versions;
-- we use the ALTER TABLE … DROP COLUMN syntax (supported since SQLite 3.35.0).
-- If this fails on an older SQLite, the column stays as-is (harmless).

ALTER TABLE theses DROP COLUMN banner_path;