我想检查数据库是否存在，并且我已经从互联网上找到了一些代码。

private boolean checkDataBase(){

SQLiteDatabase checkDB = null;

try{

String myPath = DB_PATH + DB_NAME;

checkDB = SQLiteDatabase.openDatabase(myPath, null,SQLiteDatabase.OPEN_READONLY);

}catch(SQLiteException e){

//database does't exist yet.

}

if(checkDB != null){

checkDB.close();

}

return checkDB != null ? true : false;

}

但我收到一个错误..无法打开文件

为什么它不起作用？

: sqlite returned: error code = 14, msg = cannot open file at line 27703 of [8609a15dfa], db=/data/data/com.testing.abcde/databases/scj

: sqlite returned: error code = 14, msg = os_unix.c: open() at line 27703 -"" errno=2 path=/data/data/com.testing.abcde/databases/scj, db=/data/data/com.testing.abcde/databases/scj

: sqlite3_open_v2("/data/data/com.testing.abcde/databases/scj", &handle, 1, NULL) failed

: Failed to open the database. closing it.

: android.database.sqlite.SQLiteCantOpenDatabaseException: unable to open database file

:   at android.database.sqlite.SQLiteDatabase.dbopen(Native Method)

:   at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:1013)

:   at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:986)

:   at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:962)

:   at com.lkland.softkeyboard.easytype.SQLite.checkDataBase(SQLite.java:80)

:   at com.lkland.softkeyboard.easytype.SQLite.createDataBase(SQLite.java:55)

您应该接受有关previos问题的一些答案，以便获得更多新答案。

如果Android数据库存在，则可能重复查询！

我使用此代码，它似乎运行良好：

// Where DB_PATH is /data/data/com.testing.abcde/databases/scj

// and DB_NAME is name.db

public boolean checkDBExists() {

File dbFile = new File(DB_PATH + DB_NAME);

return dbFile.exists();

}

您将需要import java.io.File;或提供对File类的完整引用。