在sqlite3中，可以结合ATTACH [1]和CREATE TABLE。 2]命令：

首先，打开bDB数据库，然后执行以下语句：

  ATTACH DATABASEmyother.dbAS aDB;之后，您可以使用CREATE TABLE语法： 






  CREATE TABLE newTableInDB1 AS SELECT * FROM aDB.oldTableInMyOtherDB; 
 
这会将数据复制到您的新数据库。 
如果你想合并数据，还有一个INSERT [3]语句，但是你需要像这样引用你的字段：
  INSERT INTO newtable（field1，field2）
 SELECT otherfield1，otherfield2 FROM aDB.oldTableInMyOtherDB; 
 
参考文献：
 

 [1] a href =http://www.sqlite.org/lang_attach.html> http://www.sqlite.org/lang_attach.html  
 

 [2]  http://www.sqlite.org/lang_createtable.html  
 

 [3]  http://www.sqlite.org/lang_insert.html  
 
I want to copy table from aDB to another bDB. 

So I made a method.
I think open 2 database and Using insert query will work but I don't know detail way.
-(void)copyDatabaseTableSoruceFileName:(NSString *)source CopyFileName:(NSString *)copy
{
sqlite3 *sourceDatabase=NULL;
sqlite3 *copyDatabase=NULL;

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask,YES);
NSString* documentDir = [paths objectAtIndex:0];

//source
    [self copyFileIfNeed:source path:documentDir];

NSString *SourceDBPath = [documentDir stringByAppendingPathComponent:source];
if( sqlite3_open([SourceDBPath UTF8String],&sourceDatabase)!= SQLITE_OK )
{
    NSLog(@"DB File Open Error :%@", SourceDBPath);
   sourceDatabase = NULL;
}
//copy    
[self copyFileIfNeed:copy path:documentDir];

NSString *CopyDBPath = [documentDir stringByAppendingPathComponent:copy];
if( sqlite3_open([CopyDBPath UTF8String],&copyDatabase)!= SQLITE_OK )
{
    NSLog(@"DB File Open Error :%@", CopyDBPath);
    copyDatabase = NULL;
}

//source to copy


 // How in this area?


}

Is it right? and how to make more ? //source to copy area.

in sqlite3, you can combine the ATTACH[1] and CREATE TABLE .. AS[2] commands:

first, you are opening the "bDB" database, and then execute the following statement:
ATTACH DATABASE "myother.db" AS aDB;

After that, you can use the CREATE TABLE syntax:
CREATE TABLE newTableInDB1 AS SELECT * FROM aDB.oldTableInMyOtherDB;

This will "copy" the data over to your new database.
If you want to merge the data, there is also an INSERT[3] statement, but with that you will need to reference your fields like this:
INSERT INTO newtable (field1,field2) 
  SELECT otherfield1,otherfield2 FROM aDB.oldTableInMyOtherDB;

References:

[1] http://www.sqlite.org/lang_attach.html

[2] http://www.sqlite.org/lang_createtable.html

[3] http://www.sqlite.org/lang_insert.html