SPI_push
Description
SPI_push should be called before executing another procedure that might itself wish to use SPI. AfterSPI_push, SPI is no longer in a"connected" state, and SPI function calls will be rejected unless a freshSPI_connect is done. This ensures a clean separation between your procedure's SPI state and that of another procedure you call. After the other procedure returns, callSPI_pop to restore access to your own SPI state.
Note thatSPI_execute and related functions automatically do the equivalent ofSPI_push before passing control back to the SQL execution engine, so it is not necessary for you to worry about this when using those functions. Only when you are directly calling arbitrary code that might containSPI_connect calls do you need to issueSPI_push andSPI_pop.