Обсуждение: why can't see the updated value after SPI_execute("update ....", false, 1);

Поиск
Список
Период
Сортировка

why can't see the updated value after SPI_execute("update ....", false, 1);

От
sunpeng
Дата:
First I use SPI_execute("update ....
  bool succ;
   SPI_connect();
    int ret = SPI_execute("update ....where uid = 1", false, 1);//later will add error processing
    if (ret == SPI_OK_UPDATE && SPI_processed == 1) {
        succ = true;
   }
   SPI_finish();
 
Then I use SPI_execute("select .....where uid = 1", ....

    SPI_connect();
    int ret = SPI_execute("select .....where uid = 1", true, 1);//later will add error processing
    if (ret == SPI_OK_SELECT && SPI_processed == 1) {          
           HeapTuple tuple;
           tuple = SPI_tuptable->vals[0];
              ...
           datum = heap_getattr(tuple,attrno,SPI_tuptable->tupdesc,&isnull);
           ....
    }
the datum doesn't change, why ?

Re: why can't see the updated value after SPI_execute("update ....", false, 1);

От
Tom Lane
Дата:
sunpeng <bluevaley@gmail.com> writes:
> First I use SPI_execute("update ....
>   bool succ;
>    SPI_connect();
>     int ret = SPI_execute("update ....where uid = 1", false, 1);//later will
> add error processing
>     if (ret == SPI_OK_UPDATE && SPI_processed == 1) {
>         succ = true;
>    }
>    SPI_finish();

> Then I use SPI_execute("select .....where uid = 1", ....

>     SPI_connect();
>     int ret = SPI_execute("select .....where uid = 1", true, 1);//later will
> add error processing
>     if (ret == SPI_OK_SELECT && SPI_processed == 1) {
>            HeapTuple tuple;
>            tuple = SPI_tuptable->vals[0];
>               ...
>            datum = heap_getattr(tuple,attrno,SPI_tuptable->tupdesc,&isnull);
>            ....
>     }
> the datum doesn't change, why ?

You're missing a CommandCounterIncrement() call between the two actions.
If you hadn't passed read_only = true to the second SPI_execute, it
would have done one for you.

            regards, tom lane

Re: why can't see the updated value after SPI_execute("update ....", false, 1);

От
sunpeng
Дата:
I then added , yet it still doesn't work.



2010/9/12 Tom Lane <tgl@sss.pgh.pa.us>
sunpeng <bluevaley@gmail.com> writes:
> First I use SPI_execute("update ....
>   bool succ;
>    SPI_connect();
>     int ret = SPI_execute("update ....where uid = 1", false, 1);//later will
> add error processing
>     if (ret == SPI_OK_UPDATE && SPI_processed == 1) {
>         succ = true;
>    }
>    SPI_finish();

> Then I use SPI_execute("select .....where uid = 1", ....

>     SPI_connect();
>     int ret = SPI_execute("select .....where uid = 1", true, 1);//later will
> add error processing
>     if (ret == SPI_OK_SELECT && SPI_processed == 1) {
>            HeapTuple tuple;
>            tuple = SPI_tuptable->vals[0];
>               ...
>            datum = heap_getattr(tuple,attrno,SPI_tuptable->tupdesc,&isnull);
>            ....
>     }
> the datum doesn't change, why ?

You're missing a CommandCounterIncrement() call between the two actions.
If you hadn't passed read_only = true to the second SPI_execute, it
would have done one for you.

                       regards, tom lane