Best practice with B4A to sync MSSQL tables with Android Sqlite

Start with this tutorial: Connect Android to MS SQL Server Tutorial

Hi Erel,

Thanks, I go for it... and testing now...
Im got error if I try to transfer big tables, few data comes ok:

httputils_getstring (B4A line: 93)
Return File.GetText(HttpUtilsService.TempFolder, SuccessfulUrls.Get(URL))
java.lang.OutOfMemoryError


at java.lang.AbstractStringBuilder.enlargeBuffer(AbstractStringBuilder.java:94)
at java.lang.AbstractStringBuilder.append0(AbstractStringBuilder.java:114)
at java.lang.StringBuilder.append(StringBuilder.java:249)
at anywheresoftware.b4a.objects.streams.File$TextReaderWrapper.ReadAll(File.java:568)
at anywheresoftware.b4a.objects.streams.File.GetText(File.java:209)
at ifw.infowarefvm.httputils._getstring(httputils.java:173)
at ifw.infowarefvm.main._jobdone(main.java:378)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at anywheresoftware.b4a.BA.raiseEvent2(BA.java:167)
at anywheresoftware.b4a.keywords.Common.CallSub4(Common.java:797)
at anywheresoftware.b4a.keywords.Common.CallSub2(Common.java:782)
at ifw.infowarefvm.httputilsservice._processnexttask(httputilsservice.java:249)
at ifw.infowarefvm.httputilsservice._response_streamfinish(httputilsservice.java:350)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at anywheresoftware.b4a.BA.raiseEvent2(BA.java:167)
at anywheresoftware.b4a.BA$3.run(BA.java:303)
at android.os.Handler.handleCallback(Handler.java:605)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:4514)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:790)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:557)
at dalvik.system.NativeStart.main(Native Method)

Seems like you are trying to read a huge string. There isn't enough memory for that. You should instead call Job.GetInputStream and read it one line after another (with TextReader).

Probably thats it.

Im using the HTTPUtils to make it easy... Probably for such large tables, may I will need to page the records requests for the data... using OFFSET like comands in the query....

What you suggest?

Many Thanks Erel, and congratulations for the nice job you done!

Maybe its better than try receive such huge amount of data at same time...

What you suggest?

Click to expand...

Here:

You should instead call Job.GetInputStream and read it one line after another (with TextReader).

Click to expand...

Thanks!

Another newb question:

Im using HttpUtils, I tried to get tables with this commands:

HttpUtils.PostString("Job1", ServerUrl, "SELECT * FROM TAB1")
HttpUtils.PostString("Job2", ServerUrl, "SELECT * FROM TAB2")

Expecting that after the JobDone the code resumes from the sub that started the 1st PostString, but its not happening, the second PostString does not fire...

I see a sample that work only calling a poststring from a JobDone, other samples not, with dim, Initialize and such that seems working the way I expected...

Any advise will be great, in the best way to load consecutive tables...

Many Thanks in Advance.

You should use HttpUtils2 instead of HttpUtils. HttpUtils2 supports multiple jobs.

.

I just found the problem:

Commas "," in as a content of a MSSQL field like a address (returned in a response):

"SAO PAULO STREET, 1233"

can cause a error in the listofvalues of DBUTILS?

SQL.ExecNonQuery2(sb.ToString, listOfValues)

In this case, how can I best deal with it?

Thanks.

Just tested without commas...

It seems there is no effect on DBUtils...

I will investigate more.

Just forget it...

DBUTILS its doing fine, and its all right. Its a problem in my DB.

Thanks