Hi,
Here's an updated patch.
I'm still not too fond of the logic in spi.c, but I can't see a better
way to do this. If someone sees a better way, I'm not going to object.
I also made some changes to the SQL functions now that we have a
different API. The previous code pushed and popped snapshots quite heavily.
I'd also like to see more regression tests for SQL functions, but I'm
going to submit my suggestions as a separate patch.
Regards,
Marko Tiikkaja
*** a/src/backend/catalog/pg_proc.c
--- b/src/backend/catalog/pg_proc.c
***************
*** 755,761 **** fmgr_sql_validator(PG_FUNCTION_ARGS)
--- 755,763 ----
Oid funcoid = PG_GETARG_OID(0);
HeapTuple tuple;
Form_pg_proc proc;
+ List *raw_parsetree_list;
List *querytree_list;
+ ListCell *list_item;
bool isnull;
Datum tmp;
char *prosrc;
***************
*** 828,836 **** fmgr_sql_validator(PG_FUNCTION_ARGS)
*/
if (!haspolyarg)
{
! querytree_list = pg_parse_and_rewrite(prosrc,
!
proc->proargtypes.values,
!
proc->pronargs);
(void) check_sql_fn_retval(funcoid, proc->prorettype,
querytree_list,
NULL, NULL);
--- 830,854 ----
*/
if (!haspolyarg)
{
! /*
! * Parse and rewrite the queries in the function text.
! *
! * Even though check_sql_fn_retval is only interested
in the last
! * query, we analyze all of them here to check for any
errors.
! */
! raw_parsetree_list = pg_parse_query(prosrc);
!
! querytree_list = NIL;
! foreach(list_item, raw_parsetree_list)
! {
! Node *parsetree = (Node *) lfirst(list_item);
!
! querytree_list =
pg_analyze_and_rewrite(parsetree, prosrc,
!
proc->proargtypes.values, proc->pronargs);
! }
!
! Assert(querytree_list != NIL);
!
(void) check_sql_fn_retval(funcoid, proc->prorettype,
querytree_list,
NULL, NULL);
*** a/src/backend/executor/functions.c
--- b/src/backend/executor/functions.c
***************
*** 84,89 **** typedef struct
--- 84,90 ----
bool returnsSet; /* true if returning multiple
rows */
bool returnsTuple; /* true if returning whole tuple result
*/
bool shutdown_reg; /* true if registered shutdown callback
*/
+ bool snapshot; /* true if pushed an active
snapshot */
bool readonly_func; /* true to run in "read only" mode */
bool lazyEval; /* true if using lazyEval for
result query */
***************
*** 93,107 **** typedef struct
JunkFilter *junkFilter; /* will be NULL if function returns
VOID */
! /* head of linked list of execution_state records */
! execution_state *func_state;
} SQLFunctionCache;
typedef SQLFunctionCache *SQLFunctionCachePtr;
/* non-export function prototypes */
! static execution_state *init_execution_state(List *queryTree_list,
SQLFunctionCachePtr fcache,
bool lazyEvalOK);
static void init_sql_fcache(FmgrInfo *finfo, bool lazyEvalOK);
--- 94,107 ----
JunkFilter *junkFilter; /* will be NULL if function returns
VOID */
! List *func_state;
} SQLFunctionCache;
typedef SQLFunctionCache *SQLFunctionCachePtr;
/* non-export function prototypes */
! static List *init_execution_state(List *queryTree_list,
SQLFunctionCachePtr fcache,
bool lazyEvalOK);
static void init_sql_fcache(FmgrInfo *finfo, bool lazyEvalOK);
***************
*** 123,183 **** static void sqlfunction_destroy(DestReceiver *self);
/* Set up the list of per-query execution_state records for a SQL function */
! static execution_state *
init_execution_state(List *queryTree_list,
SQLFunctionCachePtr fcache,
bool lazyEvalOK)
{
! execution_state *firstes = NULL;
! execution_state *preves = NULL;
execution_state *lasttages = NULL;
! ListCell *qtl_item;
! foreach(qtl_item, queryTree_list)
{
! Query *queryTree = (Query *) lfirst(qtl_item);
! Node *stmt;
! execution_state *newes;
! Assert(IsA(queryTree, Query));
! if (queryTree->commandType == CMD_UTILITY)
! stmt = queryTree->utilityStmt;
! else
! stmt = (Node *) pg_plan_query(queryTree, 0, NULL);
! /* Precheck all commands for validity in a function */
! if (IsA(stmt, TransactionStmt))
! ereport(ERROR,
! (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
! /* translator: %s is a SQL statement name */
! errmsg("%s is not allowed in a SQL
function",
!
CreateCommandTag(stmt))));
! if (fcache->readonly_func && !CommandIsReadOnly(stmt))
! ereport(ERROR,
! (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
! /* translator: %s is a SQL statement name */
! errmsg("%s is not allowed in a
non-volatile function",
!
CreateCommandTag(stmt))));
! newes = (execution_state *) palloc(sizeof(execution_state));
! if (preves)
! preves->next = newes;
! else
! firstes = newes;
! newes->next = NULL;
! newes->status = F_EXEC_START;
! newes->setsResult = false; /* might change below */
! newes->lazyEval = false; /* might change below */
! newes->stmt = stmt;
! newes->qd = NULL;
! if (queryTree->canSetTag)
! lasttages = newes;
! preves = newes;
}
/*
--- 123,200 ----
/* Set up the list of per-query execution_state records for a SQL function */
! static List *
init_execution_state(List *queryTree_list,
SQLFunctionCachePtr fcache,
bool lazyEvalOK)
{
! execution_state *firstes;
! execution_state *preves;
execution_state *lasttages = NULL;
! List *eslist;
! ListCell *lc1;
! ListCell *lc2;
! List *qtlist;
! Query *queryTree;
!
! eslist = NIL;
!
! foreach(lc1, queryTree_list)
{
! qtlist = (List *) lfirst(lc1);
! firstes = NULL;
! preves = NULL;
! foreach(lc2, qtlist)
! {
! Node *stmt;
! execution_state *newes;
! queryTree = (Query *) lfirst(lc2);
! Assert(IsA(queryTree, Query));
! if (queryTree->commandType == CMD_UTILITY)
! stmt = queryTree->utilityStmt;
! else
! stmt = (Node *) pg_plan_query(queryTree, 0,
NULL);
! /* Precheck all commands for validity in a function */
! if (IsA(stmt, TransactionStmt))
! ereport(ERROR,
!
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
! /* translator: %s is a SQL statement name */
! errmsg("%s is not allowed in a
SQL function",
!
CreateCommandTag(stmt))));
!
! if (fcache->readonly_func && !CommandIsReadOnly(stmt))
! ereport(ERROR,
!
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
! /* translator: %s is a SQL statement name */
! errmsg("%s is not allowed in a
non-volatile function",
!
CreateCommandTag(stmt))));
!
! newes = (execution_state *)
palloc(sizeof(execution_state));
! if (preves)
! preves->next = newes;
! else
! firstes = newes;
!
! newes->next = NULL;
! newes->status = F_EXEC_START;
! newes->setsResult = false; /* might change
below */
! newes->lazyEval = false; /* might change below */
! newes->stmt = stmt;
! newes->qd = NULL;
! if (queryTree->canSetTag)
! lasttages = newes;
! preves = newes;
! }
! eslist = lappend(eslist, firstes);
}
/*
***************
*** 210,216 **** init_execution_state(List *queryTree_list,
}
}
! return firstes;
}
/* Initialize the SQLFunctionCache for a SQL function */
--- 227,233 ----
}
}
! return eslist;
}
/* Initialize the SQLFunctionCache for a SQL function */
***************
*** 224,230 **** init_sql_fcache(FmgrInfo *finfo, bool lazyEvalOK)
--- 241,249 ----
SQLFunctionCachePtr fcache;
Oid *argOidVect;
int nargs;
+ List *raw_parsetree_list;
List *queryTree_list;
+ ListCell *list_item;
Datum tmp;
bool isNull;
***************
*** 319,325 **** init_sql_fcache(FmgrInfo *finfo, bool lazyEvalOK)
/*
* Parse and rewrite the queries in the function text.
*/
! queryTree_list = pg_parse_and_rewrite(fcache->src, argOidVect, nargs);
/*
* Check that the function returns the type it claims to. Although in
--- 338,356 ----
/*
* Parse and rewrite the queries in the function text.
*/
! raw_parsetree_list = pg_parse_query(fcache->src);
!
! queryTree_list = NIL;
! foreach(list_item, raw_parsetree_list)
! {
! Node *parsetree = (Node *) lfirst(list_item);
!
! queryTree_list = lappend(queryTree_list,
!
pg_analyze_and_rewrite(parsetree,
!
fcache->src,
!
argOidVect,
!
nargs));
! }
/*
* Check that the function returns the type it claims to. Although in
***************
*** 342,348 **** init_sql_fcache(FmgrInfo *finfo, bool lazyEvalOK)
*/
fcache->returnsTuple = check_sql_fn_retval(foid,
rettype,
!
queryTree_list,
NULL,
&fcache->junkFilter);
--- 373,379 ----
*/
fcache->returnsTuple = check_sql_fn_retval(foid,
rettype,
!
llast(queryTree_list),
NULL,
&fcache->junkFilter);
***************
*** 374,397 **** init_sql_fcache(FmgrInfo *finfo, bool lazyEvalOK)
static void
postquel_start(execution_state *es, SQLFunctionCachePtr fcache)
{
- Snapshot snapshot;
DestReceiver *dest;
Assert(es->qd == NULL);
! /*
! * In a read-only function, use the surrounding query's snapshot;
! * otherwise take a new snapshot for each query. The snapshot should
! * include a fresh command ID so that all work to date in this
transaction
! * is visible.
! */
! if (fcache->readonly_func)
! snapshot = GetActiveSnapshot();
! else
! {
! CommandCounterIncrement();
! snapshot = GetTransactionSnapshot();
! }
/*
* If this query produces the function result, send its output to the
--- 405,415 ----
static void
postquel_start(execution_state *es, SQLFunctionCachePtr fcache)
{
DestReceiver *dest;
Assert(es->qd == NULL);
! Assert(ActiveSnapshotSet());
/*
* If this query produces the function result, send its output to the
***************
*** 415,427 **** postquel_start(execution_state *es, SQLFunctionCachePtr fcache)
if (IsA(es->stmt, PlannedStmt))
es->qd = CreateQueryDesc((PlannedStmt *) es->stmt,
fcache->src,
! snapshot,
InvalidSnapshot,
dest,
fcache->paramLI, 0);
else
es->qd = CreateUtilityQueryDesc(es->stmt,
fcache->src,
!
snapshot,
dest,
fcache->paramLI);
--- 433,446 ----
if (IsA(es->stmt, PlannedStmt))
es->qd = CreateQueryDesc((PlannedStmt *) es->stmt,
fcache->src,
!
GetActiveSnapshot(),
!
InvalidSnapshot,
dest,
fcache->paramLI, 0);
else
es->qd = CreateUtilityQueryDesc(es->stmt,
fcache->src,
!
GetActiveSnapshot(),
dest,
fcache->paramLI);
***************
*** 451,459 **** postquel_getnext(execution_state *es, SQLFunctionCachePtr
fcache)
{
bool result;
- /* Make our snapshot the active one for any called functions */
- PushActiveSnapshot(es->qd->snapshot);
-
if (es->qd->utilitystmt)
{
/* ProcessUtility needs the PlannedStmt for DECLARE CURSOR */
--- 470,475 ----
***************
*** 481,488 **** postquel_getnext(execution_state *es, SQLFunctionCachePtr
fcache)
result = (count == 0L || es->qd->estate->es_processed == 0);
}
- PopActiveSnapshot();
-
return result;
}
--- 497,502 ----
***************
*** 496,509 **** postquel_end(execution_state *es)
/* Utility commands don't need Executor. */
if (es->qd->utilitystmt == NULL)
{
- /* Make our snapshot the active one for any called functions */
- PushActiveSnapshot(es->qd->snapshot);
-
if (es->qd->operation != CMD_SELECT)
AfterTriggerEndQuery(es->qd->estate);
ExecutorEnd(es->qd);
-
- PopActiveSnapshot();
}
(*es->qd->dest->rDestroy) (es->qd->dest);
--- 510,518 ----
***************
*** 617,622 **** fmgr_sql(PG_FUNCTION_ARGS)
--- 626,633 ----
execution_state *es;
TupleTableSlot *slot;
Datum result;
+ List *eslist;
+ ListCell *eslc;
/*
* Switch to context in which the fcache lives. This ensures that
***************
*** 668,680 **** fmgr_sql(PG_FUNCTION_ARGS)
init_sql_fcache(fcinfo->flinfo, lazyEvalOK);
fcache = (SQLFunctionCachePtr) fcinfo->flinfo->fn_extra;
}
! es = fcache->func_state;
/*
* Convert params to appropriate format if starting a fresh execution.
(If
* continuing execution, we can re-use prior params.)
*/
! if (es && es->status == F_EXEC_START)
postquel_sub_params(fcache, fcinfo);
/*
--- 679,691 ----
init_sql_fcache(fcinfo->flinfo, lazyEvalOK);
fcache = (SQLFunctionCachePtr) fcinfo->flinfo->fn_extra;
}
! eslist = fcache->func_state;
/*
* Convert params to appropriate format if starting a fresh execution.
(If
* continuing execution, we can re-use prior params.)
*/
! if (linitial(eslist) && ((execution_state *) linitial(eslist))->status
== F_EXEC_START)
postquel_sub_params(fcache, fcinfo);
/*
***************
*** 687,694 **** fmgr_sql(PG_FUNCTION_ARGS)
/*
* Find first unfinished query in function.
*/
! while (es && es->status == F_EXEC_DONE)
! es = es->next;
/*
* Execute each command in the function one after another until we
either
--- 698,715 ----
/*
* Find first unfinished query in function.
*/
!
! es = NULL; /* keep compiler quiet */
! foreach(eslc, eslist)
! {
! es = (execution_state *) lfirst(eslc);
!
! while (es && es->status == F_EXEC_DONE)
! es = es->next;
!
! if (es)
! break;
! }
/*
* Execute each command in the function one after another until we
either
***************
*** 699,705 **** fmgr_sql(PG_FUNCTION_ARGS)
--- 720,746 ----
bool completed;
if (es->status == F_EXEC_START)
+ {
+ if (!fcache->readonly_func)
+ {
+ /*
+ * In a read-only function, use the surrounding
query's snapshot;
+ * otherwise take a new snapshot if we don't
have one yet. The
+ * snapshot should include a fresh command ID
so that all work to
+ * date in this transaction is visible.
+ */
+ if (!fcache->snapshot)
+ {
+ CommandCounterIncrement();
+
PushActiveSnapshot(GetTransactionSnapshot());
+ fcache->snapshot = true;
+ }
+ else
+ UpdateActiveSnapshot();
+ }
+
postquel_start(es, fcache);
+ }
completed = postquel_getnext(es, fcache);
***************
*** 726,731 **** fmgr_sql(PG_FUNCTION_ARGS)
--- 767,791 ----
if (es->status != F_EXEC_DONE)
break;
es = es->next;
+
+ if (!es)
+ {
+ eslc = lnext(eslc);
+ if (!eslc)
+ break;
+
+ es = (execution_state *) lfirst(eslc);
+
+ /* make sure we take a new snapshot for this query list
*/
+ if (!fcache->readonly_func)
+ {
+ Assert(fcache->snapshot);
+ PopActiveSnapshot();
+ fcache->snapshot = false;
+ }
+ else
+ Assert(!fcache->snapshot);
+ }
}
/*
***************
*** 794,799 **** fmgr_sql(PG_FUNCTION_ARGS)
--- 854,864 ----
PointerGetDatum(fcache));
fcache->shutdown_reg = false;
}
+
+ /* Release snapshot if we have one */
+ if (fcache->snapshot)
+ PopActiveSnapshot();
+ fcache->snapshot = false;
}
else
{
***************
*** 820,825 **** fmgr_sql(PG_FUNCTION_ARGS)
--- 885,895 ----
PointerGetDatum(fcache));
fcache->shutdown_reg = false;
}
+
+ /* Release snapshot if we have one */
+ if (fcache->snapshot)
+ PopActiveSnapshot();
+ fcache->snapshot = false;
}
}
else
***************
*** 850,855 **** fmgr_sql(PG_FUNCTION_ARGS)
--- 920,930 ----
/* Clear the tuplestore, but keep it for next time */
tuplestore_clear(fcache->tstore);
+
+ /* Release snapshot if we have one */
+ if (fcache->snapshot)
+ PopActiveSnapshot();
+ fcache->snapshot = false;
}
/*
***************
*** 858,868 **** fmgr_sql(PG_FUNCTION_ARGS)
*/
if (es == NULL)
{
! es = fcache->func_state;
! while (es)
{
! es->status = F_EXEC_START;
! es = es->next;
}
}
--- 933,946 ----
*/
if (es == NULL)
{
! foreach(eslc, fcache->func_state)
{
! es = (execution_state *) lfirst(eslc);
! while (es)
! {
! es->status = F_EXEC_START;
! es = es->next;
! }
}
}
***************
*** 913,931 **** sql_exec_error_callback(void *arg)
{
execution_state *es;
int query_num;
! es = fcache->func_state;
query_num = 1;
! while (es)
{
! if (es->qd)
{
! errcontext("SQL function \"%s\" statement %d",
! fcache->fname, query_num);
! break;
}
- es = es->next;
- query_num++;
}
if (es == NULL)
{
--- 991,1014 ----
{
execution_state *es;
int query_num;
+ ListCell *lc;
! es = NULL; /* keep compiler quiet */
query_num = 1;
! foreach(lc, fcache->func_state)
{
! es = (execution_state *) lfirst(lc);
! while (es)
{
! if (es->qd)
! {
! errcontext("SQL function \"%s\"
statement %d",
! fcache->fname,
query_num);
! break;
! }
! es = es->next;
! query_num++;
}
}
if (es == NULL)
{
***************
*** 956,973 **** static void
ShutdownSQLFunction(Datum arg)
{
SQLFunctionCachePtr fcache = (SQLFunctionCachePtr) DatumGetPointer(arg);
! execution_state *es = fcache->func_state;
! while (es != NULL)
{
! /* Shut down anything still running */
! if (es->status == F_EXEC_RUN)
! postquel_end(es);
! /* Reset states to START in case we're called again */
! es->status = F_EXEC_START;
! es = es->next;
}
/* Release tuplestore if we have one */
if (fcache->tstore)
tuplestore_end(fcache->tstore);
--- 1039,1067 ----
ShutdownSQLFunction(Datum arg)
{
SQLFunctionCachePtr fcache = (SQLFunctionCachePtr) DatumGetPointer(arg);
! execution_state *es;
! ListCell *lc;
! foreach(lc, fcache->func_state)
{
! es = (execution_state *) lfirst(lc);
!
! while (es)
! {
! /* Shut down anything still running */
! if (es->status == F_EXEC_RUN)
! postquel_end(es);
! /* Reset states to START in case we're called again */
! es->status = F_EXEC_START;
! es = es->next;
! }
}
+ /* Release snapshot if we have one */
+ if (fcache->snapshot)
+ PopActiveSnapshot();
+ fcache->snapshot = false;
+
/* Release tuplestore if we have one */
if (fcache->tstore)
tuplestore_end(fcache->tstore);
*** a/src/backend/executor/spi.c
--- b/src/backend/executor/spi.c
***************
*** 1768,1774 **** _SPI_execute_plan(SPIPlanPtr plan, ParamListInfo paramLI,
Oid my_lastoid = InvalidOid;
SPITupleTable *my_tuptable = NULL;
int res = 0;
! bool have_active_snap = ActiveSnapshotSet();
ErrorContextCallback spierrcontext;
CachedPlan *cplan = NULL;
ListCell *lc1;
--- 1768,1774 ----
Oid my_lastoid = InvalidOid;
SPITupleTable *my_tuptable = NULL;
int res = 0;
! bool use_single_snap;
ErrorContextCallback spierrcontext;
CachedPlan *cplan = NULL;
ListCell *lc1;
***************
*** 1781,1786 **** _SPI_execute_plan(SPIPlanPtr plan, ParamListInfo paramLI,
--- 1781,1798 ----
spierrcontext.previous = error_context_stack;
error_context_stack = &spierrcontext;
+ if (read_only || snapshot != InvalidSnapshot)
+ {
+ if (snapshot != InvalidSnapshot)
+ PushActiveSnapshot(snapshot);
+ else if (read_only && ActiveSnapshotSet())
+ PushActiveSnapshot(GetActiveSnapshot());
+
+ use_single_snap = true;
+ }
+ else
+ use_single_snap = false;
+
foreach(lc1, plan->plancache_list)
{
CachedPlanSource *plansource = (CachedPlanSource *) lfirst(lc1);
***************
*** 1802,1813 **** _SPI_execute_plan(SPIPlanPtr plan, ParamListInfo paramLI,
stmt_list = plansource->plan->stmt_list;
}
foreach(lc2, stmt_list)
{
Node *stmt = (Node *) lfirst(lc2);
bool canSetTag;
DestReceiver *dest;
- bool pushed_active_snap = false;
_SPI_current->processed = 0;
_SPI_current->lastoid = InvalidOid;
--- 1814,1827 ----
stmt_list = plansource->plan->stmt_list;
}
+ if (!use_single_snap)
+ PushActiveSnapshot(GetTransactionSnapshot());
+
foreach(lc2, stmt_list)
{
Node *stmt = (Node *) lfirst(lc2);
bool canSetTag;
DestReceiver *dest;
_SPI_current->processed = 0;
_SPI_current->lastoid = InvalidOid;
***************
*** 1848,1895 **** _SPI_execute_plan(SPIPlanPtr plan, ParamListInfo paramLI,
/*
* If not read-only mode, advance the command counter
before each
! * command.
*/
if (!read_only)
CommandCounterIncrement();
dest = CreateDestReceiver(canSetTag ? DestSPI :
DestNone);
- if (snapshot == InvalidSnapshot)
- {
- /*
- * Default read_only behavior is to use the
entry-time
- * ActiveSnapshot, if any; if read-write, grab
a full new
- * snap.
- */
- if (read_only)
- {
- if (have_active_snap)
- {
-
PushActiveSnapshot(GetActiveSnapshot());
- pushed_active_snap = true;
- }
- }
- else
- {
-
PushActiveSnapshot(GetTransactionSnapshot());
- pushed_active_snap = true;
- }
- }
- else
- {
- /*
- * We interpret read_only with a specified
snapshot to be
- * exactly that snapshot, but read-write means
use the snap
- * with advancing of command ID.
- */
- if (read_only)
- PushActiveSnapshot(snapshot);
- else
- PushUpdatedSnapshot(snapshot);
- pushed_active_snap = true;
- }
-
if (IsA(stmt, PlannedStmt) &&
((PlannedStmt *) stmt)->utilityStmt == NULL)
{
--- 1862,1877 ----
/*
* If not read-only mode, advance the command counter
before each
! * command and update the snapshot.
*/
if (!read_only)
+ {
CommandCounterIncrement();
+ UpdateActiveSnapshot();
+ }
dest = CreateDestReceiver(canSetTag ? DestSPI :
DestNone);
if (IsA(stmt, PlannedStmt) &&
((PlannedStmt *) stmt)->utilityStmt == NULL)
{
***************
*** 1925,1933 **** _SPI_execute_plan(SPIPlanPtr plan, ParamListInfo paramLI,
res = SPI_OK_UTILITY;
}
- if (pushed_active_snap)
- PopActiveSnapshot();
-
/*
* The last canSetTag query sets the status values
returned to the
* caller. Be careful to free any tuptables not
returned, to
--- 1907,1912 ----
***************
*** 1970,1975 **** _SPI_execute_plan(SPIPlanPtr plan, ParamListInfo paramLI,
--- 1949,1958 ----
fail:
+ /* Pop the last snapshot off the stack if we pushed one */
+ if (!read_only || ActiveSnapshotSet())
+ PopActiveSnapshot();
+
/* We no longer need the cached plan refcount, if any */
if (cplan)
ReleaseCachedPlan(cplan, true);
*** a/src/backend/tcop/postgres.c
--- b/src/backend/tcop/postgres.c
***************
*** 505,552 **** client_read_ended(void)
}
}
-
- /*
- * Parse a query string and pass it through the rewriter.
- *
- * A list of Query nodes is returned, since the string might contain
- * multiple queries and/or the rewriter might expand one query to several.
- *
- * NOTE: this routine is no longer used for processing interactive queries,
- * but it is still needed for parsing of SQL function bodies.
- */
- List *
- pg_parse_and_rewrite(const char *query_string, /* string to execute */
- Oid *paramTypes, /* parameter
types */
- int numParams) /* number of
parameters */
- {
- List *raw_parsetree_list;
- List *querytree_list;
- ListCell *list_item;
-
- /*
- * (1) parse the request string into a list of raw parse trees.
- */
- raw_parsetree_list = pg_parse_query(query_string);
-
- /*
- * (2) Do parse analysis and rule rewrite.
- */
- querytree_list = NIL;
- foreach(list_item, raw_parsetree_list)
- {
- Node *parsetree = (Node *) lfirst(list_item);
-
- querytree_list = list_concat(querytree_list,
-
pg_analyze_and_rewrite(parsetree,
-
query_string,
-
paramTypes,
-
numParams));
- }
-
- return querytree_list;
- }
-
/*
* Do raw parsing (only).
*
--- 505,510 ----
*** a/src/backend/tcop/pquery.c
--- b/src/backend/tcop/pquery.c
***************
*** 170,180 **** ProcessQuery(PlannedStmt *plan,
elog(DEBUG3, "ProcessQuery");
/*
- * Must always set a snapshot for plannable queries.
- */
- PushActiveSnapshot(GetTransactionSnapshot());
-
- /*
* Create the QueryDesc object
*/
queryDesc = CreateQueryDesc(plan, sourceText,
--- 170,175 ----
***************
*** 234,241 **** ProcessQuery(PlannedStmt *plan,
/* Now take care of any queued AFTER triggers */
AfterTriggerEndQuery(queryDesc->estate);
- PopActiveSnapshot();
-
/*
* Now, we close down all the scans and free allocated resources.
*/
--- 229,234 ----
***************
*** 1220,1225 **** PortalRunMulti(Portal portal, bool isTopLevel,
--- 1213,1219 ----
char *completionTag)
{
ListCell *stmtlist_item;
+ bool pushed_snap = false;
/*
* If the destination is DestRemoteExecute, change to DestNone. The
***************
*** 1262,1267 **** PortalRunMulti(Portal portal, bool isTopLevel,
--- 1256,1270 ----
if (log_executor_stats)
ResetUsage();
+ /* if no snapshot is set, grab a new one */
+ if (!pushed_snap)
+ {
+ PushActiveSnapshot(GetTransactionSnapshot());
+ pushed_snap = true;
+ }
+ else
+ UpdateActiveSnapshot();
+
if (pstmt->canSetTag)
{
/* statement can set tag string */
***************
*** 1291,1301 **** PortalRunMulti(Portal portal, bool isTopLevel,
--- 1294,1318 ----
*
* These are assumed canSetTag if they're the only stmt
in the
* portal.
+ *
+ * NotifyStmt is the only utility statement allowed in
a list of
+ * rewritten queries, and it doesn't need a snapshot so
we don't
+ * need to worry about it. However, if the list has
only one
+ * statement and it's a utility statement, we are not
allowed to
+ * take a snapshot. See the first comment in
PortalRunUtility().
*/
if (list_length(portal->stmts) == 1)
+ {
+ Assert(!pushed_snap);
+
PortalRunUtility(portal, stmt, isTopLevel,
dest, completionTag);
+ }
else
+ {
+ Assert(IsA(stmt, NotifyStmt));
+
PortalRunUtility(portal, stmt, isTopLevel,
altdest, NULL);
+ }
}
/*
***************
*** 1313,1318 **** PortalRunMulti(Portal portal, bool isTopLevel,
--- 1330,1338 ----
MemoryContextDeleteChildren(PortalGetHeapMemory(portal));
}
+ if (pushed_snap)
+ PopActiveSnapshot();
+
/*
* If a command completion tag was supplied, use it. Otherwise use the
* portal's commandTag as the default completion tag.
*** a/src/backend/utils/time/snapmgr.c
--- b/src/backend/utils/time/snapmgr.c
***************
*** 305,313 **** PushUpdatedSnapshot(Snapshot snapshot)
* elsewhere, so make a new copy to scribble on.
*/
newsnap = CopySnapshot(snapshot);
- newsnap->curcid = GetCurrentCommandId(false);
PushActiveSnapshot(newsnap);
}
/*
--- 305,326 ----
* elsewhere, so make a new copy to scribble on.
*/
newsnap = CopySnapshot(snapshot);
PushActiveSnapshot(newsnap);
+ UpdateActiveSnapshot();
+ }
+
+ /*
+ * UpdateActiveSnapshot
+ *
+ * Update the current CID of the active snapshot.
+ */
+ void
+ UpdateActiveSnapshot(void)
+ {
+ Assert(ActiveSnapshotSet());
+
+ ActiveSnapshot->as_snap->curcid = GetCurrentCommandId(false);
}
/*
*** a/src/include/tcop/tcopprot.h
--- b/src/include/tcop/tcopprot.h
***************
*** 45,52 **** typedef enum
extern int log_statement;
- extern List *pg_parse_and_rewrite(const char *query_string,
- Oid *paramTypes, int numParams);
extern List *pg_parse_query(const char *query_string);
extern List *pg_analyze_and_rewrite(Node *parsetree, const char *query_string,
Oid *paramTypes, int numParams);
--- 45,50 ----
*** a/src/include/utils/snapmgr.h
--- b/src/include/utils/snapmgr.h
***************
*** 29,34 **** extern void SnapshotSetCommandId(CommandId curcid);
--- 29,35 ----
extern void PushActiveSnapshot(Snapshot snapshot);
extern void PushUpdatedSnapshot(Snapshot snapshot);
+ extern void UpdateActiveSnapshot(void);
extern void PopActiveSnapshot(void);
extern Snapshot GetActiveSnapshot(void);
extern bool ActiveSnapshotSet(void);
--
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