function openDatabase():void
{
var dbFile:File = File.applicationStorageDirectory.resolvePath("database.db");
connection = new SQLConnection();
connection.addEventListener(SQLEvent.OPEN, onOpen);
connection.openAsync(dbFile, "create");
}
i used this code in AIR to create connection and it's working but where is the database file??
where is the applicationStorageDirectory??
It's platform dependent (Mac, Windows, etc.). If you print out the value of "File.applicationStorageDirectory.nativePath", it will give you the fully-specified path on the filesystem of your current platform.
Related
I am using a cloud backup/sync service (SpiderOak) which automatically Syncs folders across several computers / devices.
I am trying to figure out a way to automatically sync all my databases across my work computer and personal laptop, without actually needing to backup/restore from one instance to the other.
So what I am thinking of is to create a new sql instance on my laptop which is identical to my work desktop instance, then to pick both SQL Server directories in Program Files to sync with each other using SpiderOak (the whole root SQL Server folders).
Will this be enough for my two instances to Sync with each other? Meaning if I create a new database on my computer at work, will I see this database on my laptop when I open SQL Server Database Management Studio?
I am almost sure if databases already exist they will sync with each other (since the root folders contain the mdf & ldf files - but correct me if I am wrong). however, I am not sure if a new database will be created if it doesn't already exist on one of the machines.
Is there any other folders that I need to sync other than the ones I specified already?
You could use Sql Sync Framework, you can download it here
some more readfood
It works for Sql Server 2005
Download and import references and include with the default ones:
using System.Data.Sql;
using System.Data.SqlClient;
using Microsoft.Synchronization;
using Microsoft.Synchronization.Data;
using Microsoft.Synchronization.Data.SqlServer;
using System.Diagnostics;
using System.Reflection;
using System.Net;
Than the actual code:
private void SyncTables()
{
SqlConnection ConStringOnline = new SqlConnection("connstring");
SqlConnection ConStringOffline = new SqlConnection("connString");
SyncOrchestrator sync = new SyncOrchestrator();
sync.Direction = SyncDirectionOrder.Download; //or DownloadAndUpload
//the 'scope1' is important, read more about it in the articles
var provider1 = new SqlSyncProvider("scope1", ConStringOnline);
var provider2 = new SqlSyncProvider("scope1", ConStringOffline);
PrepareServerForProvisioning(provider1);
PrepareClientForProvisioning(provider2, ConStringOnline);
sync.LocalProvider = provider2;
sync.RemoteProvider = provider1;
sync.Synchronize();
}
private static void PrepareServerForProvisioning(SqlSyncProvider provider)
{
SqlConnection connection = (SqlConnection)provider.Connection;
SqlSyncScopeProvisioning config = new SqlSyncScopeProvisioning(connection);
if (!config.ScopeExists(provider.ScopeName))
{
DbSyncScopeDescription scopeDesc = new DbSyncScopeDescription(provider.ScopeName);
scopeDesc.Tables.Add(SqlSyncDescriptionBuilder.GetDescriptionForTable("TABLENAME", connection));
config.PopulateFromScopeDescription(scopeDesc);
config.SetCreateTableDefault(DbSyncCreationOption.CreateOrUseExisting);
config.Apply();
}
}
private static void PrepareClientForProvisioning(SqlSyncProvider provider, SqlConnection sourceConnection)
{
SqlSyncScopeProvisioning config = new SqlSyncScopeProvisioning((SqlConnection)provider.Connection);
if (!config.ScopeExists(provider.ScopeName))
{
DbSyncScopeDescription scopeDesc = SqlSyncDescriptionBuilder.GetDescriptionForScope(provider.ScopeName, sourceConnection);
config.PopulateFromScopeDescription(scopeDesc);
config.Apply();
}
}
The downside of using Sync Framework: It is a pain in the a** to add these prerequisites to your application before publishing, no problem if you just use an application for yourself or for your company, but when you would like to publish it online it is a bit harder. I already had a topic about that
However, when using tools like InnoScript, you can install the prerequisites easily while installing the application. Here is how.
Now for the ScopeName: It is important that you don't use twice the same name, I believe. I had multiple tables so I just named them scope1,scope2,scope3,scope4. Apparently Sync Framework does the rest of the work for you. It also automatically adds _tracking tables to your database, this is just metadata to store information to synchronize properly.
I'm just learning to use SQLite and I was curious if such is possible:
Encryption of the database file?
Password protect opening of the database?
PS. I know that there is this "SQLite Encryption Extension (SEE).", but according to the documentation, "The SEE is licensed software...." and "The cost of a perpetual source code license for SEE is US $2000."
SQLite has hooks built-in for encryption which are not used in the normal distribution, but here are a few implementations I know of:
SEE - The official implementation.
wxSQLite - A wxWidgets style C++ wrapper that also implements SQLite's encryption.
SQLCipher - Uses openSSL's libcrypto to implement.
SQLiteCrypt - Custom implementation, modified API.
botansqlite3 - botansqlite3 is an encryption codec for SQLite3 that can use any algorithms in Botan for encryption.
sqleet - another encryption implementation, using ChaCha20/Poly1305 primitives. Note that wxSQLite mentioned above can use this as a crypto provider.
The SEE and SQLiteCrypt require the purchase of a license.
Disclosure: I created botansqlite3.
You can password protect SQLite3 DB.
For the first time before doing any operations, set password as follows.
SQLiteConnection conn = new SQLiteConnection("Data Source=MyDatabase.sqlite;Version=3;");
conn.SetPassword("password");
conn.open();
then next time you can access it like
conn = new SQLiteConnection("Data Source=MyDatabase.sqlite;Version=3;Password=password;");
conn.Open();
This wont allow any GUI editor to view Your data.
Later if you wish to change the password, use conn.ChangePassword("new_password");
To reset or remove password, use conn.ChangePassword(String.Empty);
The .net library System.Data.SQLite also provides for encryption.
You can get sqlite3.dll file with encryption support from http://system.data.sqlite.org/.
1 - Go to http://system.data.sqlite.org/index.html/doc/trunk/www/downloads.wiki and download one of the packages. .NET version is irrelevant here.
2 - Extract SQLite.Interop.dll from package and rename it to sqlite3.dll. This DLL supports encryption via plaintext passwords or encryption keys.
The mentioned file is native and does NOT require .NET framework. It might need Visual C++ Runtime depending on the package you have downloaded.
UPDATE
This is the package that I've downloaded for 32-bit development: http://system.data.sqlite.org/blobs/1.0.94.0/sqlite-netFx40-static-binary-Win32-2010-1.0.94.0.zip
Keep in mind, the following is not intended to be a substitute for a proper security solution.
After playing around with this for four days, I've put together a solution using only the open source System.Data.SQLite package from NuGet. I don't know how much protection this provides. I'm only using it for my own course of study. This will create the DB, encrypt it, create a table, and add data.
using System.Data.SQLite;
namespace EncryptDB
{
class Program
{
static void Main(string[] args)
{
string connectionString = #"C:\Programming\sqlite3\db.db";
string passwordString = "password";
byte[] passwordBytes = GetBytes(passwordString);
SQLiteConnection.CreateFile(connectionString);
SQLiteConnection conn = new SQLiteConnection("Data Source=" + connectionString + ";Version=3;");
conn.SetPassword(passwordBytes);
conn.Open();
SQLiteCommand sqlCmd = new SQLiteCommand("CREATE TABLE data(filename TEXT, filepath TEXT, filelength INTEGER, directory TEXT)", conn);
sqlCmd.ExecuteNonQuery();
sqlCmd = new SQLiteCommand("INSERT INTO data VALUES('name', 'path', 200, 'dir')", conn);
sqlCmd.ExecuteNonQuery();
conn.Close();
}
static byte[] GetBytes(string str)
{
byte[] bytes = new byte[str.Length * sizeof(char)];
bytes = System.Text.Encoding.Default.GetBytes(str);
return bytes;
}
}
}
Optionally, you can remove conn.SetPassword(passwordBytes);, and replace it with conn.ChangePassword("password"); which needs to be placed after conn.Open(); instead of before. Then you won't need the GetBytes method.
To decrypt, it's just a matter of putting the password in your connection string before the call to open.
string filename = #"C:\Programming\sqlite3\db.db";
string passwordString = "password";
SQLiteConnection conn = new SQLiteConnection("Data Source=" + filename + ";Version=3;Password=" + passwordString + ";");
conn.Open();
You can always encrypt data on the client side. Please note that not all of the data have to be encrypted because it has a performance issue.
You can use SQLite's function creation routines (PHP manual):
$db_obj->sqliteCreateFunction('Encrypt', 'MyEncryptFunction', 2);
$db_obj->sqliteCreateFunction('Decrypt', 'MyDecryptFunction', 2);
When inserting data, you can use the encryption function directly and INSERT the encrypted data or you can use the custom function and pass unencrypted data:
$insert_obj = $db_obj->prepare('INSERT INTO table (Clear, Encrypted) ' .
'VALUES (:clear, Encrypt(:data, "' . $passwordhash_str . '"))');
When retrieving data, you can also use SQL search functionality:
$select_obj = $db_obj->prepare('SELECT Clear, ' .
'Decrypt(Encrypted, "' . $passwordhash_str . '") AS PlainText FROM table ' .
'WHERE PlainText LIKE :searchterm');
Well, SEE is expensive. However SQLite has interface built-in for encryption (Pager). This means, that on top of existing code one can easily develop some encryption mechanism, does not have to be AES. Anything really.
Please see my post here: https://stackoverflow.com/a/49161716/9418360
You need to define SQLITE_HAS_CODEC=1 to enable Pager encryption. Sample code below (original SQLite source):
#ifdef SQLITE_HAS_CODEC
/*
** This function is called by the wal module when writing page content
** into the log file.
**
** This function returns a pointer to a buffer containing the encrypted
** page content. If a malloc fails, this function may return NULL.
*/
SQLITE_PRIVATE void *sqlite3PagerCodec(PgHdr *pPg){
void *aData = 0;
CODEC2(pPg->pPager, pPg->pData, pPg->pgno, 6, return 0, aData);
return aData;
}
#endif
There is a commercial version in C language for SQLite encryption using AES256 - it can also work with PHP, but it needs to be compiled with PHP and SQLite extension. It de/encrypts SQLite database file on the fly, file contents are always encrypted. Very useful.
http://www.iqx7.com/products/sqlite-encryption
I had also similar problem. Needed to store sensitive data in simple database (SQLite was the perfect choice except security). Finally I have placed database file on TrueCrypt encrypted valume.
Additional console app mounts temporary drive using TrueCrypt CLI and then starts the database application. Waits until the database application exits and then dismounts the drive again.
Maybe not suitable solution in all scenarios but for me working well ...
Application: Connecting to BigQuery using BigQuery APIs for Java
Environment: Eclipse, Windows 7
My application was running fine until last night. I've made no changes (except for restarting my computer) and my code is suddenly giving me this error:
Application name is not set. Call Builder#setApplicationName.
Thankfully I had a tar'd version of my workspace from last night. I ran a folder compare and found the local_db.bin file was different. I deleted the existing local_db.bin file and tried to run the program again. And it worked fine!
Any idea why this might have happened?
Hopefully this will help anyone else who stumbles upon this issue.
Try this to set your application name
Drive service = new Drive.Builder(httpTransport, jsonFactory, null)
.setHttpRequestInitializer(credential)
.setApplicationName("Your app name")
.build();
If you are working with only Firebase Dynamic Links without Android or iOS app
Try this.
builder.setApplicationName(firebaseUtil.getApplicationName());
FirebaseUtil is custom class add keys and application name to this class
FirebaseDynamicLinks.Builder builder = new FirebaseDynamicLinks.Builder(
GoogleNetHttpTransport.newTrustedTransport(), JacksonFactory.getDefaultInstance(), null);
// initialize with api key
FirebaseDynamicLinksRequestInitializer firebaseDynamicLinksRequestInitializer = new FirebaseDynamicLinksRequestInitializer(
firebaseUtil.getFirebaseApiKey());
builder.setFirebaseDynamicLinksRequestInitializer(firebaseDynamicLinksRequestInitializer);
builder.setApplicationName(firebaseUtil.getApplicationName());
// build dynamic links
FirebaseDynamicLinks firebasedynamiclinks = builder.build();
// create Firebase Dynamic Links request
CreateShortDynamicLinkRequest createShortLinkRequest = new CreateShortDynamicLinkRequest();
createShortLinkRequest.setLongDynamicLink(firebaseUtil.getFirebaseUrlPrefix() + "?link=" + urlToShorten);
Suffix suffix = new Suffix();
suffix.setOption(firebaseUtil.getShortSuffixOption());
createShortLinkRequest.setSuffix(suffix);
// request short url
FirebaseDynamicLinks.ShortLinks.Create request = firebasedynamiclinks.shortLinks()
.create(createShortLinkRequest);
CreateShortDynamicLinkResponse createShortDynamicLinkResponse = request.execute();
When trying to run the following in Redis using booksleeve.
using (var conn = new RedisConnection(server, port, -1, password))
{
var result = conn.Server.FlushDb(0);
result.Wait();
}
I get an error saying:
This command is not available unless the connection is created with
admin-commands enabled"
I am not sure how do i execute commands as admin? Do I need to create an a/c in db with admin access and login with that?
Updated answer for StackExchange.Redis:
var conn = ConnectionMultiplexer.Connect("localhost,allowAdmin=true");
Note also that the object created here should be created once per application and shared as a global singleton, per Marc:
Because the ConnectionMultiplexer does a lot, it is designed to be
shared and reused between callers. You should not create a
ConnectionMultiplexer per operation. It is fully thread-safe and ready
for this usage.
Basically, the dangerous commands that you don't need in routine operations, but which can cause lots of problems if used inappropriately (i.e. the equivalent of drop database in tsql, since your example is FlushDb) are protected by a "yes, I meant to do that..." flag:
using (var conn = new RedisConnection(server, port, -1, password,
allowAdmin: true)) <==== here
I will improve the error message to make this very clear and explicit.
You can also set this in C# when you're creating your multiplexer - set AllowAdmin = true
private ConnectionMultiplexer GetConnectionMultiplexer()
{
var options = ConfigurationOptions.Parse("localhost:6379");
options.ConnectRetry = 5;
options.AllowAdmin = true;
return ConnectionMultiplexer.Connect(options);
}
For those who like me faced the error:
StackExchange.Redis.RedisCommandException: This operation is not
available unless admin mode is enabled: ROLE
after upgrading StackExchange.Redis to version 2.2.4 with Sentinel connection: it's a known bug, the workaround was either to downgrade the client back or to add allowAdmin=true to the connection string and wait for the fix.
Starting from 2.2.50 public release the issue is fixed.
This is my first post to this precious website. I am a new learner of vb.net. I am working on a simple purchase project, where i got some errors. But the first thing is which baffled me is:
This is my connection string at module level, on the developed machine.
Public strCn As String = "Data Source = (local); Initial Catalog = PSys; Integrated Security = false; User ID = sa; Password = 123;"
Is it mandatory that Data Source must be the original name of the System Name. I mean If i use (local) or using ( . ), so will it work or not? Because when i copy my project to any other system for further development so every time i need to change the Data source, otherwise i get the error that: "Network-related or instance-specific error occurred......."
Kindly guide me that what i need to do.
When you are developing an application which uses a database server such as MsSQL it is not wise to install the server along with your application in every pc which is installed to. For example what are you going to do if a customer has a local network with 10 computers? Are you going to install SQL server in all 10 of them? And if so what if they need to share data?
So your best approach (based on common practice by other applications) will be to allow the user to install the SQL server where he wants and let him configure your application and point it to the server's location. If you follow that path then the configuration of your application can be in the setup application or in the application itself.
Now about the development phase, I had a similar situation in which I needed to develop the same application in two different computers. What I did was to install the SQL server in both of them with a named instance "sqlexpress" then in the application I used the
Data.SqlClient.SqlConnectionStringBuilder
class to build the connection string. I did something like this:
Public Function getDevConnectionString() As String
Dim csb As New Data.SqlClient.SqlConnectionStringBuilder(My.Settings.dbConnectionString) '<-My original cs in app settings
csb.DataSource = My.Computer.Name & "\sqlexpress"
Return csb.ConnectionString
End Function
Whenever I need a connection string I simply call getDevConnectionString() which returns the connection string based on the computer name plus the sql server instance name. For example:
Dim cs As String
#If DEBUG Then
cs = getDevConnectionString()
#Else
cs = getReleaseConnectionString()
#End If
where getReleaseConnectionString() is the function that returns your connection string configured by the customer.
Hope this point you the right direction...