SQLite DB read TBGrid while writing
lazarus / 63-Database

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phr0x · 2018-05-07 13:09

Hey there,

I have a probably fairly simple issue, just don't know where to look
for the solution that's why I am posting here.
First what I want to do:
I want to save data out of a constant stream I get via an USB
connection. And while doing so I want to be able to have a look at the
data with a TDBGrid Component and a Tchart Component.

I have no problem with saving the data coming in or displaying it as
it is. My Problem is that I want to see my Data in the Grid while I am
writing. Every time I write into the DB I open and close the
TSQL.Query and that's what I think causes the issue. When I filter my
DB to display the Results in the Grid and then afterwards continue
writing into the DB the Data shown in the Grid just dissapears again.
But I want to keep that data there to see it and use it in a chart and
for calculation.
Can you guys pinpoint me in a direction where I can get a solution for
this or do you maybe even have a solution already?

Short example:
Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i //this is
what I do on creating the formDBConnection.Connected :=
True;SQLTransaction1.Active := True;SQLQuery1.Open; //this is the
basics of the function I use to write into the DBSQLQuery1.SQL.Text :=
'INSERT INTO db (sensor) values
(:PH_val)';SQL.Query1.Params.ParamByName('PH_val').AsInteger :=
2SQLQuery.ExecSQL;SQLTransaction1.Commit; //this is the basics of the
function I use to filter and display the valus in a
gridSQLQuery1.SQL.Text := 'select * from
db';SQLQuery1.Open;SQLQUery1.Applyupdates; 
Best Regards

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JanRoza · 2018-05-07 20:59

Why not use commitretain instead of commit? That updates your datbase
without closing it.

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phr0x · 2018-06-11 18:32

Well, that solved it. Thank you very much.

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JanRoza · 2018-06-12 05:20

You're welcome!