SPIPlanPtr SPI_prepare_params(const char * command,
ParserSetupHook parserSetup,
void * parserSetupArg,
int cursorOptions) SPI_prepare_params creates and returns a prepared
statement for the specified command, but doesn't execute the command.
This function is equivalent to SPI_prepare_cursor,
with the addition that the caller can specify parser hook functions
to control the parsing of external parameter references.