Android SQLite如何判断表是否存在

public boolean tabbleIsExist(SQLiteDatabase db, String tableName){
boolean result = false;
if(tableName == null){
return false;
}
Cursor cursor = null;
try {
String sql = "select count(*) as c from Sqlite_master  where type ='table' and name ='"+tableName.trim()+"' ";
cursor = db.rawQuery(sql, null);
if(cursor.moveToNext()){
int count = cursor.getInt(0);
if(count>0){
result = true;
}
}

} catch (Exception e) {
// TODO: handle exception
}
return result;
}