not able to execute multiple queries at a time

[gopikrishnaParisa]

hi,
i was trying to execute INSERT and DELETE in a single command, but i couldn't do it using Sqlite3pp.
sample code:

query = "INSERT INTO Logs (logData) VALUES(?);"
"DELETE FROM Logs WHERE sequenceId=(SELECT MIN(sequenceId) FROM Logs)";
sqlite3pp::command cmd(clinicalDb_, query.c_str());
cmd.bind(1, (void *)&info, sizeof(info), sqlite3pp::copy);

     if ((rc = cmd.execute_all()) != NO_SQL_ERROR)
     {
        PX_ERRORF("Command Execution failed. rc = {}", rc);
     }

in this case i am getting rc value 1(SQLITE_ERROR).

if i pass some string to VALUES("some string), query executes successfully.

Please help me how to solve this.

[iwongu]

I don't remember exactly, but the bound params are applied to each statement. The second statement, DELETE, does not need a param.
Why don't you run them in separate commands?

[gopikrishnaParisa]

Hi,The reason for combining both the statements is to save some time. My app used to 20-25 requests for sec. at Max.  If i run both in separate statement, it is taking around 50 msc in avg. At this speed I would be able to store 20 records only, and I may loose some records. If I run both in single statement, the logging time is around 30-35 msec. Thank you. Sent from Yahoo Mail on Android On Mon, Sep 23, 2019 at 8:09 PM, Wongoo Lee<[email protected]> wrote: I don't remember exactly, but the bound params are applied to each statement. The second statement, DELETE, does not need a param. Why don't you run them in separate commands? — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub, or mute the thread.

[iwongu]

Can you bake the value in the sql string instead of using bind? The current execute_all method is using the same bind params for each statement in the sql string.

[snej]

@gopikrishnaParisa You should use a SQLite transaction around the entire set of changes you're making. That will make your code much, much faster. If you don't do this, SQLite inserts a transaction around every statement.

Committing a transaction is fairly slow since it has to ensure durability by flushing all writes to the physical storage device.