PostgreSQL table edit, memory consumption
lazarus / 16-Databases

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tatamata · 2020-06-16 06:01

Hello.
Dynamically created PostgreSQL table (size is not known in advance) is
queried by TSQLQuery and presented in RxDBGrid for reading, editing,
searching, filtering and exporting to spreadsheet or plain text files.
The dataset must be editable and forward/backward browseable, readonly
or unidirectional is not an option!
When underlying table is big, memory (16 GB) is completely consumed.
I need recommendations about alternative approaches - instead of
TSQLQuery I need some other way to browse/edit underlying PostgreSQL
table that will not load all rows in memory at once, but in chunks
while browsing.
Is ZTable (from ZeosDBO) a viable alternative?
Is there any other dataset components, instead of TSQLQuery, which can
browse underlying PostgreSQL table (for editing), in small chunks, not
overconsuming RAM?

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tatamata · 2020-06-16 21:35

Hi, any Lazarus Zeosdbo user to provide some recommendation/experience
in dealing with browsing/editing huge PostgreSQL tables?

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tatamata · 2020-12-02 11:57

Just to update on this topic, if anybody else will have similar issue
- I have solved my memory consumption trouble by switching from
TSQLQuery to Zeso TZTable component.
Dynamically created sql query with "crate table ...as" is executed,
resultset is saved as PostgreSQL table, which is then loaded by ZTable
component into RxDBGrid.
Indeed, Zeos TZTable does not have memory issues like SQLQuery, with
loading huge PostgreSQL table.