SPI_execute_plan_extended
SPI_execute_plan_extended — execute a statement prepared by SPI_prepare
Synopsis
int SPI_execute_plan_extended(SPIPlanPtrplan
, const SPIExecuteOptions *options
)
Description
SPI_execute_plan_extended
executes a statement prepared by SPI_prepare
or one of its siblings. This function is equivalent to SPI_execute_plan
, except that information about the parameter values to be passed to the query is presented differently, and additional execution-controlling options can be passed.
Query parameter values are represented by a ParamListInfo
struct, which is convenient for passing down values that are already available in that format. Dynamic parameter sets can also be used, via hook functions specified in ParamListInfo
.
Also, instead of always accumulating the result tuples into a SPI_tuptable
structure, tuples can be passed to a caller-supplied DestReceiver
object as they are generated by the executor. This is particularly helpful for queries that might generate many tuples, since the data can be processed on-the-fly instead of being accumulated in memory.
Arguments
SPIPlanPtr
plan
prepared statement (returned by
SPI_prepare
)const SPIExecuteOptions *
options
struct containing optional arguments
Callers should always zero out the entire options
struct, then fill whichever fields they want to set. This ensures forward compatibility of code, since any fields that are added to the struct in future will be defined to behave backwards-compatibly if they are zero. The currently available options
fields are:
ParamListInfo
params
data structure containing query parameter types and values; NULL if none
bool
read_only
true
for read-only executionbool
allow_nonatomic
true
allows non-atomic execution of CALL and DO statements (but this field is ignored unless theSPI_OPT_NONATOMIC
flag was passed toSPI_connect_ext
)bool
must_return_tuples
if
true
, raise error if the query is not of a kind that returns tuples (this does not forbid the case where it happens to return zero tuples)uint64
tcount
maximum number of rows to return, or
0
for no limitDestReceiver *
dest
DestReceiver
object that will receive any tuples emitted by the query; if NULL, result tuples are accumulated into aSPI_tuptable
structure, as inSPI_execute_plan
ResourceOwner
owner
The resource owner that will hold a reference count on the plan while it is executed. If NULL, CurrentResourceOwner is used. Ignored for non-saved plans, as SPI does not acquire reference counts on those.
Return Value
The return value is the same as for SPI_execute_plan
.
When options->dest
is NULL, SPI_processed
and SPI_tuptable
are set as in SPI_execute_plan
. When options->dest
is not NULL, SPI_processed
is set to zero and SPI_tuptable
is set to NULL. If a tuple count is required, the caller's DestReceiver
object must calculate it.