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Hi, EgonHugeist.

Ok. I completely forgot about forward only cursors.
Could you tell me what goals/todo for 7.3?

Why TZCachedResultSet exist =========================== DB native client (library) gets data from the DB server in its own format and places them in a continuous memory block. Client application (Zeoslib) gets pointer to this memory block. App could parse and show data from this memory area, but cou...

I try to rewrite our internal Foxpo 2.6 DOS app as 2-tire: client (Lazarus) and server (PostgreSQL). It have table like 'contracts' with now about 32000 records or, for example, 'clients' table. Our stuff is used to be able to view all contracts (as well as other parts of app data ) as (possibly lar...

Accordingly the memory consumptions of updateable ResultSets i think a little trick could help: A updatable RS is a cached-RS. This needs to be filled row by row. If this is done and the "native" RS returns Next=False we could close the handle with PGclear. This frees the memory in libpq....

I have reviewed the source code and could not find any problems with memory allocating/freeing. Each row is represented by a record TZRowBuffer which stores row values in 'Columns: TZByteArray' field by offsets. Strings and blobs not stored directly in row: for each string/blob TZAbstractBlob is cre...

Some extra debugging with rcUpdatable shown the following. 1. After connection etablished memory usage is 21336K . 2. After receiving data from server into NativeResultSet memory usage is 35612K , so data size is about 14276K . 3. Now we go to the last record of NativeResultSet. During this all reco...

Back to the subject... Recently I switch to using dbc layer of ZeosLib insteed of datasets, but with the same issue: with SetResultSetConcurrency( rcUpdatable ) some memory is not freed. With SetResultSetConcurrency( rcReadOnly ) memory freeing seems ok. While debugging ZeosLib I could not figure ou...

For the moment i have to pass. The Async functions work nice with DBC but with updateable RS where meta-informations are retrieved i failed. Maybe you have more success? I not fully understand about your problems with updateable RS in this case... are you talking about PGresult's metadata(fileds de...

I've recently started trying to implement async functions and SingleRowMode in Zeos by myself. So now I implemented PQsendQueryPrepared at dbc level and "async open+SingleRowMode+get first row" in TZAbstractRODataset. But during this hack I realize that IZResultSet and other classes assume...

Lazarus 1.2.6+ZEOSDBO-7.1.4+PostgreSQL Consider simple project (code below). With TZReadOnlyQuery application memory usage after open/close cycles is the same (don't grows). With TZQuery application memory usage grows with each open/close cycle and I can't find any way to free that memory . There is...

Further study showed the following. Call "stack" procedure TZAbstractRODataset.InternalOpen; ResultSet := CreateResultSet(FSQL.Statements[0].SQL, FetchRow) function TZAbstractRODataset.CreateResultSet(const SQL: string; MaxRows: Integer): IZResultSet; Result := Statement.ExecuteQueryPrepar...

"Which driver are you using for?" You mean database driver? PostgreSQL 9.3. with 'postgresql-9' protocol. Sorry for FireDAC - I mention it for example only to clarify my question. Now I read http://www.postgresql.org/docs/9.3/static/libpq-single-row-mode.html: " Ordinarily, libpq coll...

Hi! Can TZQuery or TZReadOnlyQuery fetch records on demand by configurable portions (records number). Something like http://docwiki.embarcadero.com/RADStudio/XE6/en/Fetching_Rows_%28FireDAC%29#Rowset_Fetching : "FireDAC is fetching rowsets according to the FetchOptions.Mode property: fmOnDemand...