最快和最有效的方式在Android的pre填充数据库 [英] Fastest and most efficient way to pre-populate database in Android

问题描述

如果你想pre-填充数据库（SQLite的）在Android中，这不是容易，因为人们可能认为。

If you want to pre-populate a database (SQLite) in Android, this is not that easy as one might think.

所以，我发现本教程也就是常此处引用的堆栈溢出为好。

So I found this tutorial which is often referenced here on Stack Overflow as well.

但我真的不喜欢的pre-填充数据库，因为你需要从数据库处理程序的控制和创建的文件你自己的方式。我想preFER不要碰文件系统，并让数据库处理程序做一切自己。

But I don't really like that way of pre-populating the database since you take the control from the database handler and create the files yourself. I would prefer to not touch the file system and let the database handler do everything on its own.

因此​​，我认为人们可以做的是在数据库中创建的处理程序的onCreate（）像往常一样的数据库，但随后加载从文件（.SQL）/资产，其中包含的语句来填充值：

So what I thought one could do is create the database in the database handler's onCreate() as usual but then load a file (.sql) from /assets which contains the statements to fill in the values:

INSERT INTO testTable (name, pet) VALUES ('Mike', 'Tiger');
INSERT INTO testTable (name, pet) VALUES ('Tom', 'Cat');
...

但调用execSQL（）在处理程序的onCreate（）并没有真正的工作。看来，/资产的文件不得有超过1MB的execSQL（）只执行第一条语句（迈克 - 虎）。

But calling execSQL() in the handler's onCreate() doesn't really work. It seems that the /assets file must not have more than 1MB and the execSQL() only executes the first statement (Mike - Tiger).

你会怎么做做pre-填充数据库？

What would you do do pre-populate the database?

推荐答案

我建议如下：

1. 包装所有的INSERT逻辑成一个事务（BEGIN ... COMMIT，或通过<一href="http://developer.android.com/reference/android/database/sqlite/SQLiteDatabase.html#beginTransaction()"相对=nofollow>的BeginTransaction（） ... <一个href="http://developer.android.com/reference/android/database/sqlite/SQLiteDatabase.html#endTransaction()"相对=nofollow> endTransaction（）方法的API）
2. 在前面已经提出，利用绑定API和回收对象。
3. 请不要创建索引，直到在此之后批量插入就完成了。

1. Wrap all of your INSERT logic into a transaction (BEGIN... COMMIT, or via the beginTransaction()... endTransaction() APIs)
2. As already suggested, utilize the bind APIs and recycle objects.
3. Don't create any indexes until after this bulk insert is complete.

此外看一看在sqlite3的更快的批量插入？

Additionally take a look at Faster bulk inserts in sqlite3?

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