-- Apply AFTER 2026_09_09_prescription_ai_analysis.sql and BEFORE deploying progress-aware code.
-- Additive, repeatable; encrypted model checkpoints and existing task states are unchanged.
SET @rx_ai_progress_exists = (
    SELECT COUNT(*) FROM information_schema.COLUMNS
    WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = 'zyt_prescription_ai_task' AND COLUMN_NAME = 'progress_json'
);
SET @rx_ai_progress_sql = IF(@rx_ai_progress_exists = 0,
    'ALTER TABLE `zyt_prescription_ai_task` ADD COLUMN `progress_json` VARCHAR(2048) NULL COMMENT ''Public stage and counters only, no clinical content''',
    'SET @rx_ai_progress_noop = 1'
);
PREPARE rx_ai_progress_statement FROM @rx_ai_progress_sql;
EXECUTE rx_ai_progress_statement;
DEALLOCATE PREPARE rx_ai_progress_statement;