SPI_execute_extended
SPI_execute_extended — execute a command with out-of-line parameters
Synopsis
int SPI_execute_extended(const char *command
, const SPIExecuteOptions *options
)
Description
SPI_execute_extended
executes a command that might include references to externally supplied parameters. The command text refers to a parameter as $
, and the n
options->params
object (if supplied) provides values and type information for each such symbol. Various execution options can be specified in the options
struct, too.
The options->params
object should normally mark each parameter with the PARAM_FLAG_CONST
flag, since a one-shot plan is always used for the query.
If options->dest
is not NULL, then result tuples are passed to that object as they are generated by the executor, instead of being accumulated in SPI_tuptable
. Using a caller-supplied DestReceiver
object 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
const char *
command
command string
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
ResourceOwner
owner
This field is present for consistency with
SPI_execute_plan_extended
, but it is ignored, since the plan used bySPI_execute_extended
is never saved.
Return Value
The return value is the same as for SPI_execute
.
When options->dest
is NULL, SPI_processed
and SPI_tuptable
are set as in SPI_execute
. 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.