diff options
Diffstat (limited to 'src/backend/nodes')
| -rw-r--r-- | src/backend/nodes/gen_node_support.pl | 7 | ||||
| -rw-r--r-- | src/backend/nodes/outfuncs.c | 8 | ||||
| -rw-r--r-- | src/backend/nodes/queryjumblefuncs.c | 302 | ||||
| -rw-r--r-- | src/backend/nodes/readfuncs.c | 8 |
4 files changed, 202 insertions, 123 deletions
diff --git a/src/backend/nodes/gen_node_support.pl b/src/backend/nodes/gen_node_support.pl index 77659b0f760..9ecddb14231 100644 --- a/src/backend/nodes/gen_node_support.pl +++ b/src/backend/nodes/gen_node_support.pl @@ -1039,6 +1039,11 @@ _read${n}(void) print $off "\tWRITE_UINT_FIELD($f);\n"; print $rff "\tREAD_UINT_FIELD($f);\n" unless $no_read; } + elsif ($t eq 'int64') + { + print $off "\tWRITE_INT64_FIELD($f);\n"; + print $rff "\tREAD_INT64_FIELD($f);\n" unless $no_read; + } elsif ($t eq 'uint64' || $t eq 'AclMode') { @@ -1324,7 +1329,7 @@ _jumble${n}(JumbleState *jstate, Node *node) # Node type. Squash constants if requested. if ($query_jumble_squash) { - print $jff "\tJUMBLE_ELEMENTS($f);\n" + print $jff "\tJUMBLE_ELEMENTS($f, node);\n" unless $query_jumble_ignore; } else diff --git a/src/backend/nodes/outfuncs.c b/src/backend/nodes/outfuncs.c index ceac3fd8620..eaf391fc2ab 100644 --- a/src/backend/nodes/outfuncs.c +++ b/src/backend/nodes/outfuncs.c @@ -51,6 +51,12 @@ static void outDouble(StringInfo str, double d); #define WRITE_UINT_FIELD(fldname) \ appendStringInfo(str, " :" CppAsString(fldname) " %u", node->fldname) +/* Write a signed integer field (anything written with INT64_FORMAT) */ +#define WRITE_INT64_FIELD(fldname) \ + appendStringInfo(str, \ + " :" CppAsString(fldname) " " INT64_FORMAT, \ + node->fldname) + /* Write an unsigned integer field (anything written with UINT64_FORMAT) */ #define WRITE_UINT64_FIELD(fldname) \ appendStringInfo(str, " :" CppAsString(fldname) " " UINT64_FORMAT, \ @@ -647,6 +653,8 @@ _outA_Expr(StringInfo str, const A_Expr *node) WRITE_NODE_FIELD(lexpr); WRITE_NODE_FIELD(rexpr); + WRITE_LOCATION_FIELD(rexpr_list_start); + WRITE_LOCATION_FIELD(rexpr_list_end); WRITE_LOCATION_FIELD(location); } diff --git a/src/backend/nodes/queryjumblefuncs.c b/src/backend/nodes/queryjumblefuncs.c index d1e82a63f09..31f97151977 100644 --- a/src/backend/nodes/queryjumblefuncs.c +++ b/src/backend/nodes/queryjumblefuncs.c @@ -21,6 +21,11 @@ * tree(s) generated from the query. The executor can then use this value * to blame query costs on the proper queryId. * + * Arrays of two or more constants and PARAM_EXTERN parameters are "squashed" + * and contribute only once to the jumble. This has the effect that queries + * that differ only on the length of such lists have the same queryId. + * + * * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group * Portions Copyright (c) 1994, Regents of the University of California * @@ -56,16 +61,18 @@ int compute_query_id = COMPUTE_QUERY_ID_AUTO; bool query_id_enabled = false; static JumbleState *InitJumble(void); -static uint64 DoJumble(JumbleState *jstate, Node *node); +static int64 DoJumble(JumbleState *jstate, Node *node); static void AppendJumble(JumbleState *jstate, const unsigned char *value, Size size); static void FlushPendingNulls(JumbleState *jstate); static void RecordConstLocation(JumbleState *jstate, - int location, bool squashed); + bool extern_param, + int location, int len); static void _jumbleNode(JumbleState *jstate, Node *node); -static void _jumbleElements(JumbleState *jstate, List *elements); -static void _jumbleA_Const(JumbleState *jstate, Node *node); static void _jumbleList(JumbleState *jstate, Node *node); +static void _jumbleElements(JumbleState *jstate, List *elements, Node *node); +static void _jumbleParam(JumbleState *jstate, Node *node); +static void _jumbleA_Const(JumbleState *jstate, Node *node); static void _jumbleVariableSetStmt(JumbleState *jstate, Node *node); static void _jumbleRangeTblEntry_eref(JumbleState *jstate, RangeTblEntry *rte, @@ -141,12 +148,12 @@ JumbleQuery(Query *query) * If we are unlucky enough to get a hash of zero, use 1 instead for * normal statements and 2 for utility queries. */ - if (query->queryId == UINT64CONST(0)) + if (query->queryId == INT64CONST(0)) { if (query->utilityStmt) - query->queryId = UINT64CONST(2); + query->queryId = INT64CONST(2); else - query->queryId = UINT64CONST(1); + query->queryId = INT64CONST(1); } return jstate; @@ -185,6 +192,7 @@ InitJumble(void) jstate->clocations_count = 0; jstate->highest_extern_param_id = 0; jstate->pending_nulls = 0; + jstate->has_squashed_lists = false; #ifdef USE_ASSERT_CHECKING jstate->total_jumble_len = 0; #endif @@ -197,7 +205,7 @@ InitJumble(void) * Jumble the given Node using the given JumbleState and return the resulting * jumble hash. */ -static uint64 +static int64 DoJumble(JumbleState *jstate, Node *node) { /* Jumble the given node */ @@ -207,10 +215,14 @@ DoJumble(JumbleState *jstate, Node *node) if (jstate->pending_nulls > 0) FlushPendingNulls(jstate); + /* Squashed list found, reset highest_extern_param_id */ + if (jstate->has_squashed_lists) + jstate->highest_extern_param_id = 0; + /* Process the jumble buffer and produce the hash value */ - return DatumGetUInt64(hash_any_extended(jstate->jumble, - jstate->jumble_len, - 0)); + return DatumGetInt64(hash_any_extended(jstate->jumble, + jstate->jumble_len, + 0)); } /* @@ -256,10 +268,10 @@ AppendJumbleInternal(JumbleState *jstate, const unsigned char *item, if (unlikely(jumble_len >= JUMBLE_SIZE)) { - uint64 start_hash; + int64 start_hash; - start_hash = DatumGetUInt64(hash_any_extended(jumble, - JUMBLE_SIZE, 0)); + start_hash = DatumGetInt64(hash_any_extended(jumble, + JUMBLE_SIZE, 0)); memcpy(jumble, &start_hash, sizeof(start_hash)); jumble_len = sizeof(start_hash); } @@ -373,15 +385,17 @@ FlushPendingNulls(JumbleState *jstate) /* - * Record location of constant within query string of query tree that is - * currently being walked. + * Record the location of some kind of constant within a query string. + * These are not only bare constants but also expressions that ultimately + * constitute a constant, such as those inside casts and simple function + * calls; if extern_param, then it corresponds to a PARAM_EXTERN Param. * - * 'squashed' signals that the constant represents the first or the last - * element in a series of merged constants, and everything but the first/last - * element contributes nothing to the jumble hash. + * If length is -1, it indicates a single such constant element. If + * it's a positive integer, it indicates the length of a squashable + * list of them. */ static void -RecordConstLocation(JumbleState *jstate, int location, bool squashed) +RecordConstLocation(JumbleState *jstate, bool extern_param, int location, int len) { /* -1 indicates unknown or undefined location */ if (location >= 0) @@ -396,9 +410,15 @@ RecordConstLocation(JumbleState *jstate, int location, bool squashed) sizeof(LocationLen)); } jstate->clocations[jstate->clocations_count].location = location; - /* initialize lengths to -1 to simplify third-party module usage */ - jstate->clocations[jstate->clocations_count].squashed = squashed; - jstate->clocations[jstate->clocations_count].length = -1; + + /* + * Lengths are either positive integers (indicating a squashable + * list), or -1. + */ + Assert(len > -1 || len == -1); + jstate->clocations[jstate->clocations_count].length = len; + jstate->clocations[jstate->clocations_count].squashed = (len > -1); + jstate->clocations[jstate->clocations_count].extern_param = extern_param; jstate->clocations_count++; } } @@ -407,47 +427,74 @@ RecordConstLocation(JumbleState *jstate, int location, bool squashed) * Subroutine for _jumbleElements: Verify a few simple cases where we can * deduce that the expression is a constant: * - * - Ignore a possible wrapping RelabelType and CoerceViaIO. - * - If it's a FuncExpr, check that the function is an implicit + * - See through any wrapping RelabelType and CoerceViaIO layers. + * - If it's a FuncExpr, check that the function is a builtin * cast and its arguments are Const. - * - Otherwise test if the expression is a simple Const. + * - Otherwise test if the expression is a simple Const or a + * PARAM_EXTERN param. */ static bool -IsSquashableConst(Node *element) +IsSquashableConstant(Node *element) { - if (IsA(element, RelabelType)) - element = (Node *) ((RelabelType *) element)->arg; - - if (IsA(element, CoerceViaIO)) - element = (Node *) ((CoerceViaIO *) element)->arg; - - if (IsA(element, FuncExpr)) +restart: + switch (nodeTag(element)) { - FuncExpr *func = (FuncExpr *) element; - ListCell *temp; + case T_RelabelType: + /* Unwrap RelabelType */ + element = (Node *) ((RelabelType *) element)->arg; + goto restart; - if (func->funcformat != COERCE_IMPLICIT_CAST && - func->funcformat != COERCE_EXPLICIT_CAST) - return false; + case T_CoerceViaIO: + /* Unwrap CoerceViaIO */ + element = (Node *) ((CoerceViaIO *) element)->arg; + goto restart; - if (func->funcid > FirstGenbkiObjectId) - return false; + case T_Const: + return true; - foreach(temp, func->args) - { - Node *arg = lfirst(temp); + case T_Param: + return castNode(Param, element)->paramkind == PARAM_EXTERN; - if (!IsA(arg, Const)) /* XXX we could recurse here instead */ - return false; - } + case T_FuncExpr: + { + FuncExpr *func = (FuncExpr *) element; + ListCell *temp; - return true; - } + if (func->funcformat != COERCE_IMPLICIT_CAST && + func->funcformat != COERCE_EXPLICIT_CAST) + return false; - if (!IsA(element, Const)) - return false; + if (func->funcid > FirstGenbkiObjectId) + return false; - return true; + /* + * We can check function arguments recursively, being careful + * about recursing too deep. At each recursion level it's + * enough to test the stack on the first element. (Note that + * I wasn't able to hit this without bloating the stack + * artificially in this function: the parser errors out before + * stack size becomes a problem here.) + */ + foreach(temp, func->args) + { + Node *arg = lfirst(temp); + + if (!IsA(arg, Const)) + { + if (foreach_current_index(temp) == 0 && + stack_is_too_deep()) + return false; + else if (!IsSquashableConstant(arg)) + return false; + } + } + + return true; + } + + default: + return false; + } } /* @@ -457,39 +504,33 @@ IsSquashableConst(Node *element) * Return value indicates if squashing is possible. * * Note that this function searches only for explicit Const nodes with - * possibly very simple decorations on top, and does not try to simplify - * expressions. + * possibly very simple decorations on top and PARAM_EXTERN parameters, + * and does not try to simplify expressions. */ static bool -IsSquashableConstList(List *elements, Node **firstExpr, Node **lastExpr) +IsSquashableConstantList(List *elements) { ListCell *temp; - /* - * If squashing is disabled, or the list is too short, we don't try to - * squash it. - */ + /* If the list is too short, we don't try to squash it. */ if (list_length(elements) < 2) return false; foreach(temp, elements) { - if (!IsSquashableConst(lfirst(temp))) + if (!IsSquashableConstant(lfirst(temp))) return false; } - *firstExpr = linitial(elements); - *lastExpr = llast(elements); - return true; } #define JUMBLE_NODE(item) \ _jumbleNode(jstate, (Node *) expr->item) -#define JUMBLE_ELEMENTS(list) \ - _jumbleElements(jstate, (List *) expr->list) +#define JUMBLE_ELEMENTS(list, node) \ + _jumbleElements(jstate, (List *) expr->list, node) #define JUMBLE_LOCATION(location) \ - RecordConstLocation(jstate, expr->location, false) + RecordConstLocation(jstate, false, expr->location, -1) #define JUMBLE_FIELD(item) \ do { \ if (sizeof(expr->item) == 8) \ @@ -516,42 +557,6 @@ do { \ #include "queryjumblefuncs.funcs.c" -/* - * We jumble lists of constant elements as one individual item regardless - * of how many elements are in the list. This means different queries - * jumble to the same query_id, if the only difference is the number of - * elements in the list. - */ -static void -_jumbleElements(JumbleState *jstate, List *elements) -{ - Node *first, - *last; - - if (IsSquashableConstList(elements, &first, &last)) - { - /* - * If this list of elements is squashable, keep track of the location - * of its first and last elements. When reading back the locations - * array, we'll see two consecutive locations with ->squashed set to - * true, indicating the location of initial and final elements of this - * list. - * - * For the limited set of cases we support now (implicit coerce via - * FuncExpr, Const) it's fine to use exprLocation of the 'last' - * expression, but if more complex composite expressions are to be - * supported (e.g., OpExpr or FuncExpr as an explicit call), more - * sophisticated tracking will be needed. - */ - RecordConstLocation(jstate, exprLocation(first), true); - RecordConstLocation(jstate, exprLocation(last), true); - } - else - { - _jumbleNode(jstate, (Node *) elements); - } -} - static void _jumbleNode(JumbleState *jstate, Node *node) { @@ -593,26 +598,6 @@ _jumbleNode(JumbleState *jstate, Node *node) break; } - /* Special cases to handle outside the automated code */ - switch (nodeTag(expr)) - { - case T_Param: - { - Param *p = (Param *) node; - - /* - * Update the highest Param id seen, in order to start - * normalization correctly. - */ - if (p->paramkind == PARAM_EXTERN && - p->paramid > jstate->highest_extern_param_id) - jstate->highest_extern_param_id = p->paramid; - } - break; - default: - break; - } - /* Ensure we added something to the jumble buffer */ Assert(jstate->total_jumble_len > prev_jumble_len); } @@ -648,6 +633,79 @@ _jumbleList(JumbleState *jstate, Node *node) } } +/* + * We try to jumble lists of expressions as one individual item regardless + * of how many elements are in the list. This is know as squashing, which + * results in different queries jumbling to the same query_id, if the only + * difference is the number of elements in the list. + * + * We allow constants and PARAM_EXTERN parameters to be squashed. To normalize + * such queries, we use the start and end locations of the list of elements in + * a list. + */ +static void +_jumbleElements(JumbleState *jstate, List *elements, Node *node) +{ + bool normalize_list = false; + + if (IsSquashableConstantList(elements)) + { + if (IsA(node, ArrayExpr)) + { + ArrayExpr *aexpr = (ArrayExpr *) node; + + if (aexpr->list_start > 0 && aexpr->list_end > 0) + { + RecordConstLocation(jstate, + false, + aexpr->list_start + 1, + (aexpr->list_end - aexpr->list_start) - 1); + normalize_list = true; + jstate->has_squashed_lists = true; + } + } + } + + if (!normalize_list) + { + _jumbleNode(jstate, (Node *) elements); + } +} + +/* + * We store the highest param ID of extern params. This can later be used + * to start the numbering of the placeholder for squashed lists. + */ +static void +_jumbleParam(JumbleState *jstate, Node *node) +{ + Param *expr = (Param *) node; + + JUMBLE_FIELD(paramkind); + JUMBLE_FIELD(paramid); + JUMBLE_FIELD(paramtype); + /* paramtypmode and paramcollid are ignored */ + + if (expr->paramkind == PARAM_EXTERN) + { + /* + * At this point, only external parameter locations outside of + * squashable lists will be recorded. + */ + RecordConstLocation(jstate, true, expr->location, -1); + + /* + * Update the highest Param id seen, in order to start normalization + * correctly. + * + * Note: This value is reset at the end of jumbling if there exists a + * squashable list. See the comment in the definition of JumbleState. + */ + if (expr->paramid > jstate->highest_extern_param_id) + jstate->highest_extern_param_id = expr->paramid; + } +} + static void _jumbleA_Const(JumbleState *jstate, Node *node) { diff --git a/src/backend/nodes/readfuncs.c b/src/backend/nodes/readfuncs.c index 64d3a09f765..48b5d13b9b6 100644 --- a/src/backend/nodes/readfuncs.c +++ b/src/backend/nodes/readfuncs.c @@ -68,6 +68,12 @@ token = pg_strtok(&length); /* get field value */ \ local_node->fldname = atoui(token) +/* Read a signed integer field (anything written using INT64_FORMAT) */ +#define READ_INT64_FIELD(fldname) \ + token = pg_strtok(&length); /* skip :fldname */ \ + token = pg_strtok(&length); /* get field value */ \ + local_node->fldname = strtoi64(token, NULL, 10) + /* Read an unsigned integer field (anything written using UINT64_FORMAT) */ #define READ_UINT64_FIELD(fldname) \ token = pg_strtok(&length); /* skip :fldname */ \ @@ -520,6 +526,8 @@ _readA_Expr(void) READ_NODE_FIELD(lexpr); READ_NODE_FIELD(rexpr); + READ_LOCATION_FIELD(rexpr_list_start); + READ_LOCATION_FIELD(rexpr_list_end); READ_LOCATION_FIELD(location); READ_DONE(); |