SPI_execute_plan_extended
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 execution -
bool
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 limit -
DestReceiver *
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.