STRING，STRING(255)还是VARCHAR(255)？

Question

我使用knex并有一个MySql db表，该表是用以下方式创建的：

exports.up = function (knex, Promise) {
    return knex.schema.table("members", (table) => {
        table.string("member_activation_hash", 255);
        table.dateTime("member_activation_sent_at");
    });
};

exports.up = function(knex) {
    return knex.schema.raw(
        "ALTER TABLE `members` CHANGE `member_activation_hash` `user_activation_hash` STRING DEFAULT NULL",
        "ALTER TABLE `members` CHANGE `member_activation_sent_at` `user_activation_sent_at` datetime DEFAULT NULL"
    );
};

exports.up = function(knex) {
    return knex.schema.raw(
        "ALTER TABLE `members` RENAME COLUMN `member_activation_hash` TO `user_activation_hash`",
        "ALTER TABLE `members` RENAME COLUMN `member_activation_sent_at` TO `user_activation_sent_at`"
    );
};

Answer 1

只需重命名列：

ALTER TABLE `members` RENAME COLUMN `member_activation_hash` TO `user_activation_hash`

请参阅此处的文档