iotlcm/server/resource/migrations/20260920_card_channel_assoc_chan_key.sql

-- card_channel_assoc.channel_id historically mixed primary IDs and numeric channel keys.
-- Store the actual t_sim_channels.chan_key so every environment resolves associations identically.
ALTER TABLE `card_channel_assoc`
    MODIFY COLUMN `channel_id` VARCHAR(64) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NOT NULL COMMENT '通道编号';