[RESOLVED] SQLite3 and two transaction
lazarus / 16-Databases

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rise_nak · 2011-06-10 13:06

Hello,
Is it possible to put on form TSQLite3Connection (for example called
SQLite3Conn1) and two TSQLTransactions with database=TSQLite3Conn1 and
using it parallel?
When I was trying to do this I got an error 'cannot start transaction
within a transaction'.
When I add second TSQLite3Connection and set property datatbase of one
of the transactions to SQLite3Conn2 I got an error that database file
is locked.
I know that it is possible to use two transactions parallel in
Firebird but is it possible in SQLite3?

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Lacak2 · 2011-06-14 07:14

AFAIK it is not possible. Active Transaction lock database file, so
other processes (connections) can not access that file in parallel.
SQLite is primary designed as single user, single process embeded
database engine.
http://www.sqlite.org/faq.html#q5
(but may be, that I am wrong in this understanding   )

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garlar27 · 2011-06-14 15:26

AFAIR:
        An SQLite table can be read by many applications at the same
time but only one can write on it at the same time.

        I had that problem before and I don't remember how I got rid
off of it. you need to pay attention to the transactions'
configuration or change the way you work.

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rise_nak · 2011-06-16 12:03

Thank you very much for help. I changed database engine to Firebird
and after some little modification in sql querys everythink is ok.
SQLite was bad choice for my program, I think with Firebird the will
be no more with DB engine.