1. PHP implementation for modifying table field types
PHP
$table->integer('shop_id')->comment('店铺ID')->change();
PHP
$table->bigInteger('shop_id')->default(0)->comment('店铺ID')->change();
2. However, when viewing the DDL in Navicat for MySQL, there were no changes. Even after closing the connection and the database, reopening them showed that there were still no changes. Finally, I had to close Navicat for MySQL and reopen it. The changes finally appeared. See Figure 1.

SQL
`shop_id` int NOT NULL COMMENT '店铺ID',
SQL
`shop_id` bigint NOT NULL DEFAULT '0' COMMENT '店铺ID',
