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-rw-r--r--src/backend/access/nbtree/nbtree.c2
-rw-r--r--src/backend/access/nbtree/nbtutils.c72
-rw-r--r--src/backend/libpq/be-secure-gssapi.c6
-rw-r--r--src/backend/parser/analyze.c90
-rw-r--r--src/backend/parser/gram.y80
5 files changed, 58 insertions, 192 deletions
diff --git a/src/backend/access/nbtree/nbtree.c b/src/backend/access/nbtree/nbtree.c
index 03a1d7b027a..fdff960c130 100644
--- a/src/backend/access/nbtree/nbtree.c
+++ b/src/backend/access/nbtree/nbtree.c
@@ -417,6 +417,8 @@ btrescan(IndexScanDesc scan, ScanKey scankey, int nscankeys,
* way, so we might as well avoid wasting cycles on acquiring page LSNs.
*
* See nbtree/README section on making concurrent TID recycling safe.
+ *
+ * Note: so->dropPin should never change across rescans.
*/
so->dropPin = (!scan->xs_want_itup &&
IsMVCCSnapshot(scan->xs_snapshot) &&
diff --git a/src/backend/access/nbtree/nbtutils.c b/src/backend/access/nbtree/nbtutils.c
index 29f0dca1b08..c71d1b6f2e1 100644
--- a/src/backend/access/nbtree/nbtutils.c
+++ b/src/backend/access/nbtree/nbtutils.c
@@ -63,7 +63,7 @@ static bool _bt_check_compare(IndexScanDesc scan, ScanDirection dir,
bool *continuescan, int *ikey);
static bool _bt_check_rowcompare(ScanKey skey,
IndexTuple tuple, int tupnatts, TupleDesc tupdesc,
- ScanDirection dir, bool *continuescan);
+ ScanDirection dir, bool forcenonrequired, bool *continuescan);
static void _bt_checkkeys_look_ahead(IndexScanDesc scan, BTReadPageState *pstate,
int tupnatts, TupleDesc tupdesc);
static int _bt_keep_natts(Relation rel, IndexTuple lastleft,
@@ -2902,10 +2902,8 @@ _bt_check_compare(IndexScanDesc scan, ScanDirection dir,
/* row-comparison keys need special processing */
if (key->sk_flags & SK_ROW_HEADER)
{
- Assert(!forcenonrequired); /* forbidden by _bt_set_startikey */
-
if (_bt_check_rowcompare(key, tuple, tupnatts, tupdesc, dir,
- continuescan))
+ forcenonrequired, continuescan))
continue;
return false;
}
@@ -3062,7 +3060,8 @@ _bt_check_compare(IndexScanDesc scan, ScanDirection dir,
*/
static bool
_bt_check_rowcompare(ScanKey skey, IndexTuple tuple, int tupnatts,
- TupleDesc tupdesc, ScanDirection dir, bool *continuescan)
+ TupleDesc tupdesc, ScanDirection dir,
+ bool forcenonrequired, bool *continuescan)
{
ScanKey subkey = (ScanKey) DatumGetPointer(skey->sk_argument);
int32 cmpresult = 0;
@@ -3102,7 +3101,11 @@ _bt_check_rowcompare(ScanKey skey, IndexTuple tuple, int tupnatts,
if (isNull)
{
- if (subkey->sk_flags & SK_BT_NULLS_FIRST)
+ if (forcenonrequired)
+ {
+ /* treating scan's keys as non-required */
+ }
+ else if (subkey->sk_flags & SK_BT_NULLS_FIRST)
{
/*
* Since NULLs are sorted before non-NULLs, we know we have
@@ -3156,8 +3159,12 @@ _bt_check_rowcompare(ScanKey skey, IndexTuple tuple, int tupnatts,
*/
Assert(subkey != (ScanKey) DatumGetPointer(skey->sk_argument));
subkey--;
- if ((subkey->sk_flags & SK_BT_REQFWD) &&
- ScanDirectionIsForward(dir))
+ if (forcenonrequired)
+ {
+ /* treating scan's keys as non-required */
+ }
+ else if ((subkey->sk_flags & SK_BT_REQFWD) &&
+ ScanDirectionIsForward(dir))
*continuescan = false;
else if ((subkey->sk_flags & SK_BT_REQBKWD) &&
ScanDirectionIsBackward(dir))
@@ -3209,7 +3216,7 @@ _bt_check_rowcompare(ScanKey skey, IndexTuple tuple, int tupnatts,
break;
}
- if (!result)
+ if (!result && !forcenonrequired)
{
/*
* Tuple fails this qual. If it's a required qual for the current
@@ -3323,24 +3330,26 @@ _bt_checkkeys_look_ahead(IndexScanDesc scan, BTReadPageState *pstate,
* current page and killed tuples thereon (generally, this should only be
* called if so->numKilled > 0).
*
- * The caller does not have a lock on the page and may or may not have the
- * page pinned in a buffer. Note that read-lock is sufficient for setting
- * LP_DEAD status (which is only a hint).
- *
- * We match items by heap TID before assuming they are the right ones to
- * delete. We cope with cases where items have moved right due to insertions.
- * If an item has moved off the current page due to a split, we'll fail to
- * find it and do nothing (this is not an error case --- we assume the item
- * will eventually get marked in a future indexscan).
+ * Caller should not have a lock on the so->currPos page, but must hold a
+ * buffer pin when !so->dropPin. When we return, it still won't be locked.
+ * It'll continue to hold whatever pins were held before calling here.
*
- * Note that if we hold a pin on the target page continuously from initially
- * reading the items until applying this function, VACUUM cannot have deleted
- * any items on the page, so the page's TIDs can't have been recycled by now.
- * There's no risk that we'll confuse a new index tuple that happens to use a
- * recycled TID with a now-removed tuple with the same TID (that used to be on
- * this same page). We can't rely on that during scans that drop pins eagerly
+ * We match items by heap TID before assuming they are the right ones to set
+ * LP_DEAD. If the scan is one that holds a buffer pin on the target page
+ * continuously from initially reading the items until applying this function
+ * (if it is a !so->dropPin scan), VACUUM cannot have deleted any items on the
+ * page, so the page's TIDs can't have been recycled by now. There's no risk
+ * that we'll confuse a new index tuple that happens to use a recycled TID
+ * with a now-removed tuple with the same TID (that used to be on this same
+ * page). We can't rely on that during scans that drop buffer pins eagerly
* (so->dropPin scans), though, so we must condition setting LP_DEAD bits on
* the page LSN having not changed since back when _bt_readpage saw the page.
+ * We totally give up on setting LP_DEAD bits when the page LSN changed.
+ *
+ * We give up much less often during !so->dropPin scans, but it still happens.
+ * We cope with cases where items have moved right due to insertions. If an
+ * item has moved off the current page due to a split, we'll fail to find it
+ * and just give up on it.
*/
void
_bt_killitems(IndexScanDesc scan)
@@ -3353,6 +3362,7 @@ _bt_killitems(IndexScanDesc scan)
OffsetNumber maxoff;
int numKilled = so->numKilled;
bool killedsomething = false;
+ Buffer buf;
Assert(numKilled > 0);
Assert(BTScanPosIsValid(so->currPos));
@@ -3369,11 +3379,11 @@ _bt_killitems(IndexScanDesc scan)
* concurrent VACUUMs from recycling any of the TIDs on the page.
*/
Assert(BTScanPosIsPinned(so->currPos));
- _bt_lockbuf(rel, so->currPos.buf, BT_READ);
+ buf = so->currPos.buf;
+ _bt_lockbuf(rel, buf, BT_READ);
}
else
{
- Buffer buf;
XLogRecPtr latestlsn;
Assert(!BTScanPosIsPinned(so->currPos));
@@ -3391,10 +3401,9 @@ _bt_killitems(IndexScanDesc scan)
}
/* Unmodified, hinting is safe */
- so->currPos.buf = buf;
}
- page = BufferGetPage(so->currPos.buf);
+ page = BufferGetPage(buf);
opaque = BTPageGetOpaque(page);
minoff = P_FIRSTDATAKEY(opaque);
maxoff = PageGetMaxOffsetNumber(page);
@@ -3511,10 +3520,13 @@ _bt_killitems(IndexScanDesc scan)
if (killedsomething)
{
opaque->btpo_flags |= BTP_HAS_GARBAGE;
- MarkBufferDirtyHint(so->currPos.buf, true);
+ MarkBufferDirtyHint(buf, true);
}
- _bt_unlockbuf(rel, so->currPos.buf);
+ if (!so->dropPin)
+ _bt_unlockbuf(rel, buf);
+ else
+ _bt_relbuf(rel, buf);
}
diff --git a/src/backend/libpq/be-secure-gssapi.c b/src/backend/libpq/be-secure-gssapi.c
index 3534f0b8111..5d98c58ffa8 100644
--- a/src/backend/libpq/be-secure-gssapi.c
+++ b/src/backend/libpq/be-secure-gssapi.c
@@ -121,9 +121,9 @@ be_gssapi_write(Port *port, const void *ptr, size_t len)
* again, so if it offers a len less than that, something is wrong.
*
* Note: it may seem attractive to report partial write completion once
- * we've successfully sent any encrypted packets. However, that can cause
- * problems for callers; notably, pqPutMsgEnd's heuristic to send only
- * full 8K blocks interacts badly with such a hack. We won't save much,
+ * we've successfully sent any encrypted packets. However, doing that
+ * expands the state space of this processing and has been responsible for
+ * bugs in the past (cf. commit d053a879b). We won't save much,
* typically, by letting callers discard data early, so don't risk it.
*/
if (len < PqGSSSendConsumed)
diff --git a/src/backend/parser/analyze.c b/src/backend/parser/analyze.c
index a16fdd65601..34f7c17f576 100644
--- a/src/backend/parser/analyze.c
+++ b/src/backend/parser/analyze.c
@@ -239,102 +239,23 @@ parse_sub_analyze(Node *parseTree, ParseState *parentParseState,
}
/*
- * setQueryLocationAndLength
- * Set query's location and length from statement and ParseState
- *
- * Some statements, like PreparableStmt, can be located within parentheses.
- * For example "(SELECT 1)" or "COPY (UPDATE ...) to x;". For those, we
- * cannot use the whole string from the statement's location or the SQL
- * string would yield incorrectly. The parser will set stmt_len, reflecting
- * the size of the statement within the parentheses. Thus, when stmt_len is
- * available, we need to use it for the Query's stmt_len.
- *
- * For other cases, the parser can't provide the length of individual
- * statements. However, we have the statement's location plus the length
- * (p_stmt_len) and location (p_stmt_location) of the top level RawStmt,
- * stored in pstate. Thus, the statement's length is the RawStmt's length
- * minus how much we've advanced in the RawStmt's string. If p_stmt_len
- * is 0, the SQL string is used up to its end.
- */
-static void
-setQueryLocationAndLength(ParseState *pstate, Query *qry, Node *parseTree)
-{
- ParseLoc stmt_len = 0;
-
- switch (nodeTag(parseTree))
- {
- case T_InsertStmt:
- qry->stmt_location = ((InsertStmt *) parseTree)->stmt_location;
- stmt_len = ((InsertStmt *) parseTree)->stmt_len;
- break;
-
- case T_DeleteStmt:
- qry->stmt_location = ((DeleteStmt *) parseTree)->stmt_location;
- stmt_len = ((DeleteStmt *) parseTree)->stmt_len;
- break;
-
- case T_UpdateStmt:
- qry->stmt_location = ((UpdateStmt *) parseTree)->stmt_location;
- stmt_len = ((UpdateStmt *) parseTree)->stmt_len;
- break;
-
- case T_MergeStmt:
- qry->stmt_location = ((MergeStmt *) parseTree)->stmt_location;
- stmt_len = ((MergeStmt *) parseTree)->stmt_len;
- break;
-
- case T_SelectStmt:
- qry->stmt_location = ((SelectStmt *) parseTree)->stmt_location;
- stmt_len = ((SelectStmt *) parseTree)->stmt_len;
- break;
-
- case T_PLAssignStmt:
- qry->stmt_location = ((PLAssignStmt *) parseTree)->location;
- break;
-
- default:
- qry->stmt_location = pstate->p_stmt_location;
- break;
- }
-
- if (stmt_len > 0)
- {
- /* Statement's length is known, use it */
- qry->stmt_len = stmt_len;
- }
- else if (pstate->p_stmt_len > 0)
- {
- /*
- * The top RawStmt's length is known, so calculate the statement's
- * length from the statement's location and the RawStmt's length and
- * location.
- */
- qry->stmt_len = pstate->p_stmt_len - (qry->stmt_location - pstate->p_stmt_location);
- }
-
- /* The calculated statement length should be calculated as positive. */
- Assert(qry->stmt_len >= 0);
-}
-
-/*
* transformTopLevelStmt -
* transform a Parse tree into a Query tree.
*
- * This function is just responsible for storing location data
- * from the RawStmt into the ParseState.
+ * This function is just responsible for transferring statement location data
+ * from the RawStmt into the finished Query.
*/
Query *
transformTopLevelStmt(ParseState *pstate, RawStmt *parseTree)
{
Query *result;
- /* Store RawStmt's length and location in pstate */
- pstate->p_stmt_len = parseTree->stmt_len;
- pstate->p_stmt_location = parseTree->stmt_location;
-
/* We're at top level, so allow SELECT INTO */
result = transformOptionalSelectInto(pstate, parseTree->stmt);
+ result->stmt_location = parseTree->stmt_location;
+ result->stmt_len = parseTree->stmt_len;
+
return result;
}
@@ -503,7 +424,6 @@ transformStmt(ParseState *pstate, Node *parseTree)
/* Mark as original query until we learn differently */
result->querySource = QSRC_ORIGINAL;
result->canSetTag = true;
- setQueryLocationAndLength(pstate, result, parseTree);
return result;
}
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 0b5652071d1..7a9b2ddddec 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -154,7 +154,6 @@ static void base_yyerror(YYLTYPE *yylloc, core_yyscan_t yyscanner,
const char *msg);
static RawStmt *makeRawStmt(Node *stmt, int stmt_location);
static void updateRawStmtEnd(RawStmt *rs, int end_location);
-static void updatePreparableStmtEnd(Node *n, int end_location);
static Node *makeColumnRef(char *colname, List *indirection,
int location, core_yyscan_t yyscanner);
static Node *makeTypeCast(Node *arg, TypeName *typename, int location);
@@ -178,7 +177,7 @@ static void insertSelectOptions(SelectStmt *stmt,
SelectLimit *limitClause,
WithClause *withClause,
core_yyscan_t yyscanner);
-static Node *makeSetOp(SetOperation op, bool all, Node *larg, Node *rarg, int location);
+static Node *makeSetOp(SetOperation op, bool all, Node *larg, Node *rarg);
static Node *doNegate(Node *n, int location);
static void doNegateFloat(Float *v);
static Node *makeAndExpr(Node *lexpr, Node *rexpr, int location);
@@ -3417,7 +3416,6 @@ CopyStmt: COPY opt_binary qualified_name opt_column_list
{
CopyStmt *n = makeNode(CopyStmt);
- updatePreparableStmtEnd($3, @4);
n->relation = NULL;
n->query = $3;
n->attlist = NIL;
@@ -12240,7 +12238,6 @@ InsertStmt:
$5->onConflictClause = $6;
$5->returningClause = $7;
$5->withClause = $1;
- $5->stmt_location = @$;
$$ = (Node *) $5;
}
;
@@ -12431,7 +12428,6 @@ DeleteStmt: opt_with_clause DELETE_P FROM relation_expr_opt_alias
n->whereClause = $6;
n->returningClause = $7;
n->withClause = $1;
- n->stmt_location = @$;
$$ = (Node *) n;
}
;
@@ -12506,7 +12502,6 @@ UpdateStmt: opt_with_clause UPDATE relation_expr_opt_alias
n->whereClause = $7;
n->returningClause = $8;
n->withClause = $1;
- n->stmt_location = @$;
$$ = (Node *) n;
}
;
@@ -12584,7 +12579,6 @@ MergeStmt:
m->joinCondition = $8;
m->mergeWhenClauses = $9;
m->returningClause = $10;
- m->stmt_location = @$;
$$ = (Node *) m;
}
@@ -12825,20 +12819,7 @@ SelectStmt: select_no_parens %prec UMINUS
;
select_with_parens:
- '(' select_no_parens ')'
- {
- SelectStmt *n = (SelectStmt *) $2;
-
- /*
- * As SelectStmt's location starts at the SELECT keyword,
- * we need to track the length of the SelectStmt within
- * parentheses to be able to extract the relevant part
- * of the query. Without this, the RawStmt's length would
- * be used and would include the closing parenthesis.
- */
- n->stmt_len = @3 - @2;
- $$ = $2;
- }
+ '(' select_no_parens ')' { $$ = $2; }
| '(' select_with_parens ')' { $$ = $2; }
;
@@ -12960,7 +12941,6 @@ simple_select:
n->groupDistinct = ($7)->distinct;
n->havingClause = $8;
n->windowClause = $9;
- n->stmt_location = @1;
$$ = (Node *) n;
}
| SELECT distinct_clause target_list
@@ -12978,7 +12958,6 @@ simple_select:
n->groupDistinct = ($7)->distinct;
n->havingClause = $8;
n->windowClause = $9;
- n->stmt_location = @1;
$$ = (Node *) n;
}
| values_clause { $$ = $1; }
@@ -12999,20 +12978,19 @@ simple_select:
n->targetList = list_make1(rt);
n->fromClause = list_make1($2);
- n->stmt_location = @1;
$$ = (Node *) n;
}
| select_clause UNION set_quantifier select_clause
{
- $$ = makeSetOp(SETOP_UNION, $3 == SET_QUANTIFIER_ALL, $1, $4, @1);
+ $$ = makeSetOp(SETOP_UNION, $3 == SET_QUANTIFIER_ALL, $1, $4);
}
| select_clause INTERSECT set_quantifier select_clause
{
- $$ = makeSetOp(SETOP_INTERSECT, $3 == SET_QUANTIFIER_ALL, $1, $4, @1);
+ $$ = makeSetOp(SETOP_INTERSECT, $3 == SET_QUANTIFIER_ALL, $1, $4);
}
| select_clause EXCEPT set_quantifier select_clause
{
- $$ = makeSetOp(SETOP_EXCEPT, $3 == SET_QUANTIFIER_ALL, $1, $4, @1);
+ $$ = makeSetOp(SETOP_EXCEPT, $3 == SET_QUANTIFIER_ALL, $1, $4);
}
;
@@ -13590,7 +13568,6 @@ values_clause:
{
SelectStmt *n = makeNode(SelectStmt);
- n->stmt_location = @1;
n->valuesLists = list_make1($3);
$$ = (Node *) n;
}
@@ -18748,47 +18725,6 @@ updateRawStmtEnd(RawStmt *rs, int end_location)
rs->stmt_len = end_location - rs->stmt_location;
}
-/*
- * Adjust a PreparableStmt to reflect that it doesn't run to the end of the
- * string.
- */
-static void
-updatePreparableStmtEnd(Node *n, int end_location)
-{
- if (IsA(n, SelectStmt))
- {
- SelectStmt *stmt = (SelectStmt *) n;
-
- stmt->stmt_len = end_location - stmt->stmt_location;
- }
- else if (IsA(n, InsertStmt))
- {
- InsertStmt *stmt = (InsertStmt *) n;
-
- stmt->stmt_len = end_location - stmt->stmt_location;
- }
- else if (IsA(n, UpdateStmt))
- {
- UpdateStmt *stmt = (UpdateStmt *) n;
-
- stmt->stmt_len = end_location - stmt->stmt_location;
- }
- else if (IsA(n, DeleteStmt))
- {
- DeleteStmt *stmt = (DeleteStmt *) n;
-
- stmt->stmt_len = end_location - stmt->stmt_location;
- }
- else if (IsA(n, MergeStmt))
- {
- MergeStmt *stmt = (MergeStmt *) n;
-
- stmt->stmt_len = end_location - stmt->stmt_location;
- }
- else
- elog(ERROR, "unexpected node type %d", (int) n->type);
-}
-
static Node *
makeColumnRef(char *colname, List *indirection,
int location, core_yyscan_t yyscanner)
@@ -19167,14 +19103,11 @@ insertSelectOptions(SelectStmt *stmt,
errmsg("multiple WITH clauses not allowed"),
parser_errposition(exprLocation((Node *) withClause))));
stmt->withClause = withClause;
-
- /* Update SelectStmt's location to the start of the WITH clause */
- stmt->stmt_location = withClause->location;
}
}
static Node *
-makeSetOp(SetOperation op, bool all, Node *larg, Node *rarg, int location)
+makeSetOp(SetOperation op, bool all, Node *larg, Node *rarg)
{
SelectStmt *n = makeNode(SelectStmt);
@@ -19182,7 +19115,6 @@ makeSetOp(SetOperation op, bool all, Node *larg, Node *rarg, int location)
n->all = all;
n->larg = (SelectStmt *) larg;
n->rarg = (SelectStmt *) rarg;
- n->stmt_location = location;
return (Node *) n;
}
generated by cgit v1.2.3 (git 2.25.1) at 2025-06-12 10:30:51 +0000