Put a type in a blob in sqlite?

[Ricky D]

Is it possible to save a map or list of types into a sqlite table?

I know I can do it easily with randomaccessfile but would like to do it in sqlite.

Regards, Ricky

 

[Erel]

The simplest solution is to use a temporary file.
- Write the objects to the file with RandomAccessFile.WriteObject.
- Read the file contents into a bytes array and store it as a blob field.

To read the data from the database you will need the opposite operations.

 

[Ricky D]

Thanks Erel I'll try that later when I'm at my place.

Regards, Ricky

 

[salmander]

The simplest solution is to use a temporary file.
- Write the objects to the file with RandomAccessFile.WriteObject.
- Read the file contents into a bytes array and store it as a blob field.

To read the data from the database you will need the opposite operations.

Erel, Can you please give me an example code for this?

 

[Erel]

I remember that I previously created an example of reading a file into a bytes array. Try searching for it.

The SQL tutorial demonstrates how to store and read BLOB fields.

 

[salmander]

This is how I am saving the MAP as a BLOB

Dim ra As RandomAccessFile
   ra.Initialize(File.DirDefaultExternal, "temp1.dat", False)
   ra.WriteObject(AllServiceOperations, False, 0)
   ra.Close
   Dim os1 As OutputStream
   Dim is1 As InputStream
   is1 = File.OpenInput(File.DirDefaultExternal, "temp1.dat")
   os1.InitializeToBytesArray(1000)
   File.Copy2(is1, os1)
   Dim bytes1() As Byte
   bytes1 = os1.ToBytesArray
   'ra.ReadBytes(bytes1, 0, bytes1.Length, 0)
   sql1.ExecNonQuery2("UPDATE tblJobs SET all_operations=? WHERE device_job_id=?", Array As Object(bytes1, device_job_id))
   File.Delete(File.DirDefaultExternal, "temp1.dat") ' deleting the temp file.

I can see the data in the database by sqlite viewer app.

I can't seem to read it and convert it to map
here is what I am trying

Dim output1() As Byte
      If sql1.IsInitialized = False Then sql1.Initialize(File.DirDefaultExternal, "jobs.db", True)
      output1 = sql1.ExecQuerySingleResult2("SELECT all_operations FROM tblJobs WHERE device_job_id=?", Array As String(device_job_id))
      Dim is1 As InputStream
      is1.InitializeFromBytesArray(output1, 0, output1.Length)
      Dim os1 As OutputStream
      os1.InitializeToBytesArray(1000)
      File.Copy2(is1, os1)
      Dim ra As RandomAccessFile

what do I do next? Please help?

 

[parijs]

Erel's example

http://www.b4x.com/forum/basic4android-getting-started-tutorials/6736-sql-tutorial.html#post39108

 

[salmander]

Erel's example

http://www.b4x.com/forum/basic4android-getting-started-tutorials/6736-sql-tutorial.html#post39108

Thanks mate, but that example still doesn't explain, how to convert to MAP.

 

[salmander]

Thanks mate, but that example still doesn't explain, how to convert to MAP.

Thank you all for the help. I have managed to solve it.