Question

我即将发布我用Titanium Alloy编写的iPhone应用程序的应用程序更新。我已经在数据库中添加了一个新列，因此我已经为它编写了一个迁移。向上迁移很简单，只需更改表以添加新列。但是，向下迁移有点担心，因为它涉及创建临时数据库，存储我需要的数据，然后删除现有数据库并使用存储的数据创建新数据库，以便保留删除列。

如何测试此代码是否正确且有效？

以下是我的迁移：

migration.up = function(migrator) {
    migrator.db.execute('ALTER TABLE ' + migrator.table + ' ADD COLUMN is_sample BOOLEAN;');
};

migration.down = function(migrator) {
    var db = migrator.db;
    var table = migrator.table;
    db.execute('CREATE TEMPORARY TABLE beers_backup(alloy_id,name,brewery,rating,percent,establishment,location,notes,date,date_string,beer_image,latitude,longitude,favourite);');
    db.execute('INSERT INTO beers_backup SELECT alloy_id,name,brewery,rating,percent,establishment,location,notes,date,date_string,beer_image,latitude,longitude,favourite FROM ' + table + ';');
    migrator.dropTable();
    migrator.createTable({
        columns: {
            "name": "text",
            "brewery": "text",
            "rating": "integer",
            "percent": "integer",
            "establishment": "text",
            "location": "text",
            "notes": "text",
            "date": "text",
            "date_string": "text",
            "beer_image": "text",
            "latitude": "integer",
            "longitude": "integer",
            "favourite": "boolean"
        },
    });
    db.execute('INSERT INTO ' + table + ' SELECT alloy_id,name,brewery,rating,percent,establishment,location,notes,date,date_string,beer_image,latitude,longitude,favourite FROM beers_backup;');
    db.execute('DROP TABLE beers_backup;');
};

Answer 1

只要您的第一个迁移文件（创建模型时创建的文件）与此处的向下迁移匹配，您就可以了。

像这样：

migration.up = function(migrator){
 migrator.createTable({
  columns: {
   "name": "text",
   "brewery": "text",
   "rating": "integer",
   "percent": "integer",
   "establishment": "text",
   "location": "text",
   "notes": "text",
   "date": "text",
   "date_string": "text",
   "beer_image": "text",
   "latitude": "integer",
   "longitude": "integer",
   "favourite": "boolean"
  }
});
};

migration.down = function(migrator) {
 migrator.droptTable();
};

此迁移文件的时间戳必须小于原始问题中列出的时间戳。

您如何测试钛合金迁移是否有效？

1 个答案: