Help with SPI...

["Cristian Prieto" <cristian@xxxxxxxxxxxxxxx>]

Hi, I will try to explain the most possible my question:

 

I'm writing a Store Procedure as a C Language Function in the Database, I need to handle a bytea (binary objetc) and store it in a modified mode in the database, I've done it in the following way:

 

PG_FUNCTION_INFO_V1(myspi);

 

Datum
myspi(PG_FUNCTION_ARGS)
{
 int ret;
 bool isnull;
 bytea *val;

 

 ret = SPI_connect();

 

 ret = SPI_exec("SELECT val FROM binary_table", 1);
 if (ret == SPI_OK_SELECT && SPI_processed > 0) {
    TupleDesc tupdesc = SPI_tuptable->tupdesc;
    SPITupleTable *tuptable = SPI_tuptable;

 

    val = DatumGetByteP(SPI_getbinval(tuptable->vals[0], tupdesc, 1, &isnull));
 }

 

/* Here I use and modified the new version of the val value */

 

// I don't know what to do here to store the new value again :(
 
 SPI_finish();
 PG_RETURN_INT32(val);
}

 

Well, the new value is really the content of a memory segment, I know I could store it again using SPI and an UPDATE statement, but that means that I need to transform the val value into a string, and I don't know the length of the string with the scape characters added.

 

Any idea in how to handle this?

 

Thanks a lot...