PostgreSQL中Insert语句如何使用，很多新手对此不是很清楚，为了帮助大家解决这个难题，下面小编将为大家详细讲解，有这方面需求的人可以来学习下，希望你能有所收获。
一、源码解读
standard_planner函数,生成PlannedStmt,其中最重要的信息是可用于后续执行SQL语句的planTree.
PlannedStmt *
standard_planner(Query *parse, int cursorOptions, ParamListInfo boundParams)
{
PlannedStmt *result;//返回结果
PlannerGlobal *glob;//全局的Plan信息-Global information for planning/optimization
double tuple_fraction;//
PlannerInfo *root;//每个Query的Plan信息-Per-query information for planning/optimization
RelOptInfo *final_rel;//Plan中的每个Relation信息-Per-relation information for planning/optimization
Path *best_path;//最优路径
Plan *top_plan;//最上层的Plan
ListCell *lp,//临时变量
*lr;
glob = makeNode(PlannerGlobal);//构建PlannerGlobal
//初始化参数
glob->boundParams = boundParams;
glob->subplans = NIL;
glob->subroots = NIL;
glob->rewindPlanIDs = NULL;
glob->finalrtable = NIL;
glob->finalrowmarks = NIL;
glob->resultRelations = NIL;
glob->nonleafResultRelations = NIL;
glob->rootResultRelations = NIL;
glob->relationOids = NIL;
glob->invalItems = NIL;
glob->paramExecTypes = NIL;
glob->lastPHId = 0;
glob->lastRowMarkId = 0;
glob->lastPlanNodeId = 0;
glob->transientPlan = false;
glob->dependsOnRole = false;
if ((cursorOptions & CURSOR_OPT_PARALLEL_OK) != 0 &&
IsUnderPostmaster &&
parse->commandType == CMD_SELECT &&
!parse->hasModifyingCTE &&
max_parallel_workers_per_gather > 0 &&
!IsParallelWorker() &&
!IsolationIsSerializable())//并行模式的判断
{
glob->maxParallelHazard = max_parallel_hazard(parse);
glob->parallelModeOK = (glob->maxParallelHazard != PROPARALLEL_UNSAFE);
}
else
{
glob->maxParallelHazard = PROPARALLEL_UNSAFE;
glob->parallelModeOK = false;
}
glob->parallelModeNeeded = glob->parallelModeOK &&
(force_parallel_mode != FORCE_PARALLEL_OFF);
if (cursorOptions & CURSOR_OPT_FAST_PLAN)
{
tuple_fraction = cursor_tuple_fraction;//使用GUC 参数
if (tuple_fraction >= 1.0)
tuple_fraction = 0.0;
else if (tuple_fraction <= 0.0)
tuple_fraction = 1e-10;
}
else
{
tuple_fraction = 0.0;
}
root = subquery_planner(glob, parse, NULL,
false, tuple_fraction);//获取PlannerInfo根节点
final_rel = fetch_upper_rel(root, UPPERREL_FINAL, NULL);//获取顶层的RelOptInfo
best_path = get_cheapest_fractional_path(final_rel, tuple_fraction);//选择最佳路径
top_plan = create_plan(root, best_path);//生成执行计划
if (cursorOptions & CURSOR_OPT_SCROLL)
{
if (!ExecSupportsBackwardScan(top_plan))
top_plan = materialize_finished_plan(top_plan);
}
if (force_parallel_mode != FORCE_PARALLEL_OFF && top_plan->parallel_safe)
{
Gather *gather = makeNode(Gather);
gather->plan.initPlan = top_plan->initPlan;
top_plan->initPlan = NIL;
gather->plan.targetlist = top_plan->targetlist;
gather->plan.qual = NIL;
gather->plan.lefttree = top_plan;
gather->plan.righttree = NULL;
gather->num_workers = 1;
gather->single_copy = true;
gather->invisible = (force_parallel_mode == FORCE_PARALLEL_REGRESS);
gather->rescan_param = -1;
gather->plan.startup_cost = top_plan->startup_cost +
parallel_setup_cost;
gather->plan.total_cost = top_plan->total_cost +
parallel_setup_cost + parallel_tuple_cost * top_plan->plan_rows;
gather->plan.plan_rows = top_plan->plan_rows;
gather->plan.plan_width = top_plan->plan_width;
gather->plan.parallel_aware = false;
gather->plan.parallel_safe = false;
root->glob->parallelModeNeeded = true;
top_plan = &gather->plan;
}
if (glob->paramExecTypes != NIL)
{
Assert(list_length(glob->subplans) == list_length(glob->subroots));
forboth(lp, glob->subplans, lr, glob->subroots)
{
Plan *subplan = (Plan *) lfirst(lp);
PlannerInfo *subroot = lfirst_node(PlannerInfo, lr);
SS_finalize_plan(subroot, subplan);
}
SS_finalize_plan(root, top_plan);
}
Assert(glob->finalrtable == NIL);
Assert(glob->finalrowmarks == NIL);
Assert(glob->resultRelations == NIL);
Assert(glob->nonleafResultRelations == NIL);
Assert(glob->rootResultRelations == NIL);
top_plan = set_plan_references(root, top_plan);
Assert(list_length(glob->subplans) == list_length(glob->subroots));
forboth(lp, glob->subplans, lr, glob->subroots)
{
Plan *subplan = (Plan *) lfirst(lp);
PlannerInfo *subroot = lfirst_node(PlannerInfo, lr);
lfirst(lp) = set_plan_references(subroot, subplan);
}
result = makeNode(PlannedStmt);
result->commandType = parse->commandType;//命令类型
result->queryId = parse->queryId;
result->hasReturning = (parse->returningList != NIL);
result->hasModifyingCTE = parse->hasModifyingCTE;
result->canSetTag = parse->canSetTag;
result->transientPlan = glob->transientPlan;
result->dependsOnRole = glob->dependsOnRole;
result->parallelModeNeeded = glob->parallelModeNeeded;
result->planTree = top_plan;//执行计划(这是后续执行SQL使用到的最重要的地方)
result->rtable = glob->finalrtable;
result->resultRelations = glob->resultRelations;
result->nonleafResultRelations = glob->nonleafResultRelations;
result->rootResultRelations = glob->rootResultRelations;
result->subplans = glob->subplans;
result->rewindPlanIDs = glob->rewindPlanIDs;
result->rowMarks = glob->finalrowmarks;
result->relationOids = glob->relationOids;
result->invalItems = glob->invalItems;
result->paramExecTypes = glob->paramExecTypes;
result->utilityStmt = parse->utilityStmt;
result->stmt_location = parse->stmt_location;
result->stmt_len = parse->stmt_len;
result->jitFlags = PGJIT_NONE;
if (jit_enabled && jit_above_cost >= 0 &&
top_plan->total_cost > jit_above_cost)
{
result->jitFlags |= PGJIT_PERFORM;
if (jit_optimize_above_cost >= 0 &&
top_plan->total_cost > jit_optimize_above_cost)
result->jitFlags |= PGJIT_OPT3;
if (jit_inline_above_cost >= 0 &&
top_plan->total_cost > jit_inline_above_cost)
result->jitFlags |= PGJIT_INLINE;
if (jit_expressions)
result->jitFlags |= PGJIT_EXPR;
if (jit_tuple_deforming)
result->jitFlags |= PGJIT_DEFORM;
}
return result;
}二、基础信息
standard_planner函数使用的数据结构、宏定义以及依赖的函数等。
数据结构/宏定义
1、PlannerGlobal
typedef struct PlannerGlobal
{
NodeTag type;
ParamListInfo boundParams;
List *subplans;
List *subroots;
Bitmapset *rewindPlanIDs;
List *finalrtable;
List *finalrowmarks;
List *resultRelations;
List *nonleafResultRelations;
List *rootResultRelations;
List *relationOids;
List *invalItems;
List *paramExecTypes;
Index lastPHId;
Index lastRowMarkId;
int lastPlanNodeId;
bool transientPlan;
bool dependsOnRole;
bool parallelModeOK;
bool parallelModeNeeded;
char maxParallelHazard;
} PlannerGlobal;2、PlannerInfo
struct AppendRelInfo;
typedef struct PlannerInfo
{
NodeTag type;
Query *parse;
PlannerGlobal *glob;
Index query_level;
struct PlannerInfo *parent_root;
List *plan_params;
Bitmapset *outer_params;
struct RelOptInfo **simple_rel_array;
int simple_rel_array_size;
RangeTblEntry **simple_rte_array;
struct AppendRelInfo **append_rel_array;
Relids all_baserels;
Relids nullable_baserels;
List *join_rel_list;
struct HTAB *join_rel_hash;
List **join_rel_level;
int join_cur_level;
List *init_plans;
List *cte_plan_ids;
List *multiexpr_params;
List *eq_classes;
List *canon_pathkeys;
List *left_join_clauses;
List *right_join_clauses;
List *full_join_clauses;
List *join_info_list;
List *append_rel_list;
List *rowMarks;
List *placeholder_list;
List *fkey_list;
List *query_pathkeys;
List *group_pathkeys;
List *window_pathkeys;
List *distinct_pathkeys;
List *sort_pathkeys;
List *part_schemes;
List *initial_rels;
List *upper_rels[UPPERREL_FINAL + 1];
struct PathTarget *upper_targets[UPPERREL_FINAL + 1];//参见UpperRelationKind
List *processed_tlist;
AttrNumber *grouping_map;
List *minmax_aggs;
MemoryContext planner_cxt;
double total_table_pages;
double tuple_fraction;
double limit_tuples;
Index qual_security_level;
InheritanceKind inhTargetKind;
bool hasJoinRTEs;
bool hasLateralRTEs;
bool hasDeletedRTEs;
bool hasHavingQual;
bool hasPseudoConstantQuals;
bool hasRecursion;
int wt_param_id;
struct Path *non_recursive_path;
Relids curOuterRels;
List *curOuterParams;
void *join_search_private;
bool partColsUpdated;
} PlannerInfo;
typedef enum UpperRelationKind
{
UPPERREL_SETOP,
UPPERREL_PARTIAL_GROUP_AGG,
UPPERREL_GROUP_AGG,
UPPERREL_WINDOW,
UPPERREL_DISTINCT,
UPPERREL_ORDERED,
UPPERREL_FINAL
} UpperRelationKind;3、RangeTblEntry
typedef enum RTEKind
{
RTE_RELATION,
RTE_SUBQUERY,
RTE_JOIN,
RTE_FUNCTION,
RTE_TABLEFUNC,
RTE_VALUES,
RTE_CTE,
RTE_NAMEDTUPLESTORE
} RTEKind;
typedef struct RangeTblEntry
{
NodeTag type;
RTEKind rtekind;
Oid relid;
char relkind;
struct TableSampleClause *tablesample;
Query *subquery;
bool security_barrier;
JoinType jointype;
List *joinaliasvars;
List *functions;
bool funcordinality;
TableFunc *tablefunc;
List *values_lists;
char *ctename;
Index ctelevelsup;
bool self_reference;
List *coltypes;
List *coltypmods;
List *colcollations;
char *enrname;
double enrtuples;
Alias *alias;
Alias *eref;
bool lateral;
bool inh;
bool inFromCl;
AclMode requiredPerms;
Oid checkAsUser;
Bitmapset *selectedCols;
Bitmapset *insertedCols;
Bitmapset *updatedCols;
List *securityQuals;
} RangeTblEntry;4、TargetEntry
typedef struct TargetEntry
{
Expr xpr;
Expr *expr;
AttrNumber resno;
char *resname;
Index ressortgroupref;
Oid resorigtbl;
AttrNumber resorigcol;
bool resjunk;
} TargetEntry;5、RelOptInfo
typedef enum RelOptKind
{
RELOPT_BASEREL,
RELOPT_JOINREL,
RELOPT_OTHER_MEMBER_REL,
RELOPT_OTHER_JOINREL,
RELOPT_UPPER_REL,
RELOPT_OTHER_UPPER_REL,
RELOPT_DEADREL
} RelOptKind;
#define IS_SIMPLE_REL(rel) \
((rel)->reloptkind == RELOPT_BASEREL || \
(rel)->reloptkind == RELOPT_OTHER_MEMBER_REL)
#define IS_JOIN_REL(rel) \
((rel)->reloptkind == RELOPT_JOINREL || \
(rel)->reloptkind == RELOPT_OTHER_JOINREL)
#define IS_UPPER_REL(rel) \
((rel)->reloptkind == RELOPT_UPPER_REL || \
(rel)->reloptkind == RELOPT_OTHER_UPPER_REL)
#define IS_OTHER_REL(rel) \
((rel)->reloptkind == RELOPT_OTHER_MEMBER_REL || \
(rel)->reloptkind == RELOPT_OTHER_JOINREL || \
(rel)->reloptkind == RELOPT_OTHER_UPPER_REL)
typedef struct RelOptInfo
{
NodeTag type;
RelOptKind reloptkind;
Relids relids;
double rows;
bool consider_startup;
bool consider_param_startup;
bool consider_parallel;
struct PathTarget *reltarget;
List *pathlist;
List *ppilist;
List *partial_pathlist;
struct Path *cheapest_startup_path;
struct Path *cheapest_total_path;
struct Path *cheapest_unique_path;
List *cheapest_parameterized_paths;
Relids direct_lateral_relids;
Relids lateral_relids;
Index relid;
Oid reltablespace;
RTEKind rtekind;
AttrNumber min_attr;
AttrNumber max_attr;
Relids *attr_needed;
int32 *attr_widths;
List *lateral_vars;
Relids lateral_referencers;
List *indexlist;
List *statlist;
BlockNumber pages;
double tuples;
double allvisfrac;
PlannerInfo *subroot;
List *subplan_params;
int rel_parallel_workers;
Oid serverid;
Oid userid;
bool useridiscurrent;
struct FdwRoutine *fdwroutine;
void *fdw_private;
List *unique_for_rels;
List *non_unique_for_rels;
List *baserestrictinfo;
QualCost baserestrictcost;
Index baserestrict_min_security;
List *joininfo;
bool has_eclass_joins;
Relids top_parent_relids;
PartitionScheme part_scheme;
int nparts;
struct PartitionBoundInfoData *boundinfo;
List *partition_qual;
struct RelOptInfo **part_rels;
List **partexprs;
List **nullable_partexprs;
List *partitioned_child_rels;
} RelOptInfo;6、Path
typedef struct Path
{
NodeTag type;
NodeTag pathtype;
RelOptInfo *parent;
PathTarget *pathtarget;
ParamPathInfo *param_info;
bool parallel_aware;
bool parallel_safe;
int parallel_workers;
double rows;
Cost startup_cost;
Cost total_cost;
List *pathkeys;
} Path;
typedef struct PathKey
{
NodeTag type;
EquivalenceClass *pk_eclass;
Oid pk_opfamily;
int pk_strategy;
bool pk_nulls_first;
} PathKey;
typedef struct PathTarget
{
NodeTag type;
List *exprs;
Index *sortgrouprefs;
QualCost cost;
int width;
} PathTarget;
#define get_pathtarget_sortgroupref(target, colno) \
((target)->sortgrouprefs ? (target)->sortgrouprefs[colno] : (Index) 0)7、ModifyTable
typedef struct ModifyTable
{
Plan plan;
CmdType operation;
bool canSetTag;
Index nominalRelation;
List *partitioned_rels;
bool partColsUpdated;
List *resultRelations;
int resultRelIndex;
int rootResultRelIndex;
List *plans;
List *withCheckOptionLists;
List *returningLists;
List *fdwPrivLists;
Bitmapset *fdwDirectModifyPlans;
List *rowMarks;
int epqParam;
OnConflictAction onConflictAction;
List *arbiterIndexes;
List *onConflictSet;
Node *onConflictWhere;
Index exclRelRTI;
List *exclRelTlist;
} ModifyTable;依赖的函数
1、grouping_planner
static void
grouping_planner(PlannerInfo *root, bool inheritance_update,
double tuple_fraction)
{
Query *parse = root->parse;
List *tlist;
int64 offset_est = 0;
int64 count_est = 0;
double limit_tuples = -1.0;
bool have_postponed_srfs = false;
PathTarget *final_target;
List *final_targets;
List *final_targets_contain_srfs;
bool final_target_parallel_safe;
RelOptInfo *current_rel;
RelOptInfo *final_rel;
ListCell *lc;
if (parse->limitCount || parse->limitOffset)
{
tuple_fraction = preprocess_limit(root, tuple_fraction,
&offset_est, &count_est);
if (count_est > 0 && offset_est >= 0)
limit_tuples = (double) count_est + (double) offset_est;
}
root->tuple_fraction = tuple_fraction;
if (parse->setOperations)
{
if (parse->sortClause)
root->tuple_fraction = 0.0;
current_rel = plan_set_operations(root);
Assert(parse->commandType == CMD_SELECT);
tlist = root->processed_tlist;
tlist = postprocess_setop_tlist(copyObject(tlist), parse->targetList);
root->processed_tlist = tlist;
final_target = current_rel->cheapest_total_path->pathtarget;
final_target_parallel_safe =
is_parallel_safe(root, (Node *) final_target->exprs);
Assert(!parse->hasTargetSRFs);
final_targets = final_targets_contain_srfs = NIL;
if (parse->rowMarks)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("%s is not allowed with UNION/INTERSECT/EXCEPT",
LCS_asString(linitial_node(RowMarkClause,
parse->rowMarks)->strength))));
Assert(parse->distinctClause == NIL);
root->sort_pathkeys = make_pathkeys_for_sortclauses(root,
parse->sortClause,
tlist);
}
else
{
PathTarget *sort_input_target;
List *sort_input_targets;
List *sort_input_targets_contain_srfs;
bool sort_input_target_parallel_safe;
PathTarget *grouping_target;
List *grouping_targets;
List *grouping_targets_contain_srfs;
bool grouping_target_parallel_safe;
PathTarget *scanjoin_target;
List *scanjoin_targets;
List *scanjoin_targets_contain_srfs;
bool scanjoin_target_parallel_safe;
bool scanjoin_target_same_exprs;
bool have_grouping;
AggClauseCosts agg_costs;
WindowFuncLists *wflists = NULL;
List *activeWindows = NIL;
grouping_sets_data *gset_data = NULL;
standard_qp_extra qp_extra;
Assert(!root->hasRecursion);
if (parse->groupingSets)
{
gset_data = preprocess_grouping_sets(root);
}
else
{
if (parse->groupClause)
parse->groupClause = preprocess_groupclause(root, NIL);
}
tlist = preprocess_targetlist(root);
root->processed_tlist = tlist;
MemSet(&agg_costs, 0, sizeof(AggClauseCosts));
if (parse->hasAggs)
{
get_agg_clause_costs(root, (Node *) tlist, AGGSPLIT_SIMPLE,
&agg_costs);
get_agg_clause_costs(root, parse->havingQual, AGGSPLIT_SIMPLE,
&agg_costs);
}
if (parse->hasWindowFuncs)
{
wflists = find_window_functions((Node *) tlist,
list_length(parse->windowClause));
if (wflists->numWindowFuncs > 0)
activeWindows = select_active_windows(root, wflists);
else
parse->hasWindowFuncs = false;
}
if (parse->hasAggs)
preprocess_minmax_aggregates(root, tlist);
if (parse->groupClause ||
parse->groupingSets ||
parse->distinctClause ||
parse->hasAggs ||
parse->hasWindowFuncs ||
parse->hasTargetSRFs ||
root->hasHavingQual)
root->limit_tuples = -1.0;
else
root->limit_tuples = limit_tuples;
qp_extra.tlist = tlist;
qp_extra.activeWindows = activeWindows;
qp_extra.groupClause = (gset_data
? (gset_data->rollups ? linitial_node(RollupData, gset_data->rollups)->groupClause : NIL)
: parse->groupClause);
current_rel = query_planner(root, tlist,
standard_qp_callback, &qp_extra);
final_target = create_pathtarget(root, tlist);
final_target_parallel_safe =
is_parallel_safe(root, (Node *) final_target->exprs);
if (parse->sortClause)
{
sort_input_target = make_sort_input_target(root,
final_target,
&have_postponed_srfs);
sort_input_target_parallel_safe =
is_parallel_safe(root, (Node *) sort_input_target->exprs);
}
else
{
sort_input_target = final_target;
sort_input_target_parallel_safe = final_target_parallel_safe;
}
if (activeWindows)
{
grouping_target = make_window_input_target(root,
final_target,
activeWindows);
grouping_target_parallel_safe =
is_parallel_safe(root, (Node *) grouping_target->exprs);
}
else
{
grouping_target = sort_input_target;
grouping_target_parallel_safe = sort_input_target_parallel_safe;
}
have_grouping = (parse->groupClause || parse->groupingSets ||
parse->hasAggs || root->hasHavingQual);
if (have_grouping)
{
scanjoin_target = make_group_input_target(root, final_target);
scanjoin_target_parallel_safe =
is_parallel_safe(root, (Node *) grouping_target->exprs);
}
else
{
scanjoin_target = grouping_target;
scanjoin_target_parallel_safe = grouping_target_parallel_safe;
}
if (parse->hasTargetSRFs)
{
split_pathtarget_at_srfs(root, final_target, sort_input_target,
&final_targets,
&final_targets_contain_srfs);
final_target = linitial_node(PathTarget, final_targets);
Assert(!linitial_int(final_targets_contain_srfs));
split_pathtarget_at_srfs(root, sort_input_target, grouping_target,
&sort_input_targets,
&sort_input_targets_contain_srfs);
sort_input_target = linitial_node(PathTarget, sort_input_targets);
Assert(!linitial_int(sort_input_targets_contain_srfs));
split_pathtarget_at_srfs(root, grouping_target, scanjoin_target,
&grouping_targets,
&grouping_targets_contain_srfs);
grouping_target = linitial_node(PathTarget, grouping_targets);
Assert(!linitial_int(grouping_targets_contain_srfs));
split_pathtarget_at_srfs(root, scanjoin_target, NULL,
&scanjoin_targets,
&scanjoin_targets_contain_srfs);
scanjoin_target = linitial_node(PathTarget, scanjoin_targets);
Assert(!linitial_int(scanjoin_targets_contain_srfs));
}
else
{
final_targets = final_targets_contain_srfs = NIL;
sort_input_targets = sort_input_targets_contain_srfs = NIL;
grouping_targets = grouping_targets_contain_srfs = NIL;
scanjoin_targets = list_make1(scanjoin_target);
scanjoin_targets_contain_srfs = NIL;
}
scanjoin_target_same_exprs = list_length(scanjoin_targets) == 1
&& equal(scanjoin_target->exprs, current_rel->reltarget->exprs);
apply_scanjoin_target_to_paths(root, current_rel, scanjoin_targets,
scanjoin_targets_contain_srfs,
scanjoin_target_parallel_safe,
scanjoin_target_same_exprs);
root->upper_targets[UPPERREL_FINAL] = final_target;
root->upper_targets[UPPERREL_WINDOW] = sort_input_target;
root->upper_targets[UPPERREL_GROUP_AGG] = grouping_target;
if (have_grouping)
{
current_rel = create_grouping_paths(root,
current_rel,
grouping_target,
grouping_target_parallel_safe,
&agg_costs,
gset_data);
if (parse->hasTargetSRFs)
adjust_paths_for_srfs(root, current_rel,
grouping_targets,
grouping_targets_contain_srfs);
}
if (activeWindows)
{
current_rel = create_window_paths(root,
current_rel,
grouping_target,
sort_input_target,
sort_input_target_parallel_safe,
tlist,
wflists,
activeWindows);
if (parse->hasTargetSRFs)
adjust_paths_for_srfs(root, current_rel,
sort_input_targets,
sort_input_targets_contain_srfs);
}
if (parse->distinctClause)
{
current_rel = create_distinct_paths(root,
current_rel);
}
}
if (parse->sortClause)
{
current_rel = create_ordered_paths(root,
current_rel,
final_target,
final_target_parallel_safe,
have_postponed_srfs ? -1.0 :
limit_tuples);
if (parse->hasTargetSRFs)
adjust_paths_for_srfs(root, current_rel,
final_targets,
final_targets_contain_srfs);
}
final_rel = fetch_upper_rel(root, UPPERREL_FINAL, NULL);
if (current_rel->consider_parallel &&
is_parallel_safe(root, parse->limitOffset) &&
is_parallel_safe(root, parse->limitCount))
final_rel->consider_parallel = true;
final_rel->serverid = current_rel->serverid;
final_rel->userid = current_rel->userid;
final_rel->useridiscurrent = current_rel->useridiscurrent;
final_rel->fdwroutine = current_rel->fdwroutine;
foreach(lc, current_rel->pathlist)
{
Path *path = (Path *) lfirst(lc);
if (parse->rowMarks)
{
path = (Path *) create_lockrows_path(root, final_rel, path,
root->rowMarks,
SS_assign_special_param(root));
}
if (limit_needed(parse))
{
path = (Path *) create_limit_path(root, final_rel, path,
parse->limitOffset,
parse->limitCount,
offset_est, count_est);
}
if (parse->commandType != CMD_SELECT && !inheritance_update)
{
List *withCheckOptionLists;
List *returningLists;
List *rowMarks;
if (parse->withCheckOptions)
withCheckOptionLists = list_make1(parse->withCheckOptions);
else
withCheckOptionLists = NIL;
if (parse->returningList)
returningLists = list_make1(parse->returningList);
else
returningLists = NIL;
if (parse->rowMarks)
rowMarks = NIL;
else
rowMarks = root->rowMarks;
path = (Path *)
create_modifytable_path(root, final_rel,
parse->commandType,
parse->canSetTag,
parse->resultRelation,
NIL,
false,
list_make1_int(parse->resultRelation),
list_make1(path),
list_make1(root),
withCheckOptionLists,
returningLists,
rowMarks,
parse->onConflict,
SS_assign_special_param(root));
}
add_path(final_rel, path);
}
if (final_rel->consider_parallel && root->query_level > 1 &&
!limit_needed(parse))
{
Assert(!parse->rowMarks && parse->commandType == CMD_SELECT);
foreach(lc, current_rel->partial_pathlist)
{
Path *partial_path = (Path *) lfirst(lc);
add_partial_path(final_rel, partial_path);
}
}
if (final_rel->fdwroutine &&
final_rel->fdwroutine->GetForeignUpperPaths)
final_rel->fdwroutine->GetForeignUpperPaths(root, UPPERREL_FINAL,
current_rel, final_rel,
NULL);
if (create_upper_paths_hook)
(*create_upper_paths_hook) (root, UPPERREL_FINAL,
current_rel, final_rel, NULL);
}
RelOptInfo *
query_planner(PlannerInfo *root, List *tlist,
query_pathkeys_callback qp_callback, void *qp_extra)
{
Query *parse = root->parse;
List *joinlist;
RelOptInfo *final_rel;
Index rti;
double total_pages;
if (parse->jointree->fromlist == NIL)
{
final_rel = build_empty_join_rel(root);
if (root->glob->parallelModeOK)
final_rel->consider_parallel =
is_parallel_safe(root, parse->jointree->quals);
add_path(final_rel, (Path *)
create_result_path(root, final_rel,
final_rel->reltarget,
(List *) parse->jointree->quals));
set_cheapest(final_rel);
root->canon_pathkeys = NIL;
(*qp_callback) (root, qp_extra);
return final_rel;
}
ModifyTablePath *
create_modifytable_path(PlannerInfo *root, RelOptInfo *rel,
CmdType operation, bool canSetTag,
Index nominalRelation, List *partitioned_rels,
bool partColsUpdated,
List *resultRelations, List *subpaths,
List *subroots,
List *withCheckOptionLists, List *returningLists,
List *rowMarks, OnConflictExpr *onconflict,
int epqParam)
{
ModifyTablePath *pathnode = makeNode(ModifyTablePath);
double total_size;
ListCell *lc;
Assert(list_length(resultRelations) == list_length(subpaths));
Assert(list_length(resultRelations) == list_length(subroots));
Assert(withCheckOptionLists == NIL ||
list_length(resultRelations) == list_length(withCheckOptionLists));
Assert(returningLists == NIL ||
list_length(resultRelations) == list_length(returningLists));
pathnode->path.pathtype = T_ModifyTable;
pathnode->path.parent = rel;
pathnode->path.pathtarget = rel->reltarget;
pathnode->path.param_info = NULL;
pathnode->path.parallel_aware = false;
pathnode->path.parallel_safe = false;
pathnode->path.parallel_workers = 0;
pathnode->path.pathkeys = NIL;
pathnode->path.startup_cost = 0;
pathnode->path.total_cost = 0;
pathnode->path.rows = 0;
total_size = 0;
foreach(lc, subpaths)
{
Path *subpath = (Path *) lfirst(lc);
if (lc == list_head(subpaths))
pathnode->path.startup_cost = subpath->startup_cost;
pathnode->path.total_cost += subpath->total_cost;
pathnode->path.rows += subpath->rows;
total_size += subpath->pathtarget->width * subpath->rows;
}
if (pathnode->path.rows > 0)
total_size /= pathnode->path.rows;
pathnode->path.pathtarget->width = rint(total_size);
pathnode->operation = operation;
pathnode->canSetTag = canSetTag;
pathnode->nominalRelation = nominalRelation;
pathnode->partitioned_rels = list_copy(partitioned_rels);
pathnode->partColsUpdated = partColsUpdated;
pathnode->resultRelations = resultRelations;
pathnode->subpaths = subpaths;
pathnode->subroots = subroots;
pathnode->withCheckOptionLists = withCheckOptionLists;
pathnode->returningLists = returningLists;
pathnode->rowMarks = rowMarks;
pathnode->onconflict = onconflict;
pathnode->epqParam = epqParam;
return pathnode;
}2、subquery_planner
PlannerInfo *
subquery_planner(PlannerGlobal *glob, Query *parse,
PlannerInfo *parent_root,
bool hasRecursion, double tuple_fraction)
{
PlannerInfo *root;//返回值
List *newWithCheckOptions;//
List *newHaving;//Having子句
bool hasOuterJoins;//是否存在Outer Join?
RelOptInfo *final_rel;//
ListCell *l;//临时变量
root = makeNode(PlannerInfo);//构造返回值
root->parse = parse;
root->glob = glob;
root->query_level = parent_root ? parent_root->query_level + 1 : 1;
root->parent_root = parent_root;
root->plan_params = NIL;
root->outer_params = NULL;
root->planner_cxt = CurrentMemoryContext;
root->init_plans = NIL;
root->cte_plan_ids = NIL;
root->multiexpr_params = NIL;
root->eq_classes = NIL;
root->append_rel_list = NIL;
root->rowMarks = NIL;
memset(root->upper_rels, 0, sizeof(root->upper_rels));
memset(root->upper_targets, 0, sizeof(root->upper_targets));
root->processed_tlist = NIL;
root->grouping_map = NULL;
root->minmax_aggs = NIL;
root->qual_security_level = 0;
root->inhTargetKind = INHKIND_NONE;
root->hasRecursion = hasRecursion;
if (hasRecursion)
root->wt_param_id = SS_assign_special_param(root);
else
root->wt_param_id = -1;
root->non_recursive_path = NULL;
root->partColsUpdated = false;
if (parse->cteList)
SS_process_ctes(root);//With 语句
if (parse->hasSubLinks)
pull_up_sublinks(root); //转换ANY/EXISTS为JOIN
inline_set_returning_functions(root);
pull_up_subqueries(root);//
if (parse->setOperations)
flatten_simple_union_all(root);
root->hasJoinRTEs = false;
root->hasLateralRTEs = false;
hasOuterJoins = false;
foreach(l, parse->rtable)
{
RangeTblEntry *rte = lfirst_node(RangeTblEntry, l);
if (rte->rtekind == RTE_JOIN)
{
root->hasJoinRTEs = true;
if (IS_OUTER_JOIN(rte->jointype))
hasOuterJoins = true;
}
if (rte->lateral)
root->hasLateralRTEs = true;
}
preprocess_rowmarks(root);
expand_inherited_tables(root);
root->hasHavingQual = (parse->havingQual != NULL);
root->hasPseudoConstantQuals = false;
parse->targetList = (List *)
preprocess_expression(root, (Node *) parse->targetList,
EXPRKIND_TARGET);
if (parse->hasTargetSRFs)
parse->hasTargetSRFs = expression_returns_set((Node *) parse->targetList);
newWithCheckOptions = NIL;
foreach(l, parse->withCheckOptions)
{
WithCheckOption *wco = lfirst_node(WithCheckOption, l);
wco->qual = preprocess_expression(root, wco->qual,
EXPRKIND_QUAL);
if (wco->qual != NULL)
newWithCheckOptions = lappend(newWithCheckOptions, wco);
}
parse->withCheckOptions = newWithCheckOptions;
parse->returningList = (List *)
preprocess_expression(root, (Node *) parse->returningList,
EXPRKIND_TARGET);
preprocess_qual_conditions(root, (Node *) parse->jointree);
parse->havingQual = preprocess_expression(root, parse->havingQual,
EXPRKIND_QUAL);
foreach(l, parse->windowClause)
{
WindowClause *wc = lfirst_node(WindowClause, l);
wc->startOffset = preprocess_expression(root, wc->startOffset,
EXPRKIND_LIMIT);
wc->endOffset = preprocess_expression(root, wc->endOffset,
EXPRKIND_LIMIT);
}
parse->limitOffset = preprocess_expression(root, parse->limitOffset,
EXPRKIND_LIMIT);
parse->limitCount = preprocess_expression(root, parse->limitCount,
EXPRKIND_LIMIT);
if (parse->onConflict)
{
parse->onConflict->arbiterElems = (List *)
preprocess_expression(root,
(Node *) parse->onConflict->arbiterElems,
EXPRKIND_ARBITER_ELEM);
parse->onConflict->arbiterWhere =
preprocess_expression(root,
parse->onConflict->arbiterWhere,
EXPRKIND_QUAL);
parse->onConflict->onConflictSet = (List *)
preprocess_expression(root,
(Node *) parse->onConflict->onConflictSet,
EXPRKIND_TARGET);
parse->onConflict->onConflictWhere =
preprocess_expression(root,
parse->onConflict->onConflictWhere,
EXPRKIND_QUAL);
}
root->append_rel_list = (List *)
preprocess_expression(root, (Node *) root->append_rel_list,
EXPRKIND_APPINFO);
foreach(l, parse->rtable)
{
RangeTblEntry *rte = lfirst_node(RangeTblEntry, l);
int kind;
ListCell *lcsq;
if (rte->rtekind == RTE_RELATION)
{
if (rte->tablesample)
rte->tablesample = (TableSampleClause *)
preprocess_expression(root,
(Node *) rte->tablesample,
EXPRKIND_TABLESAMPLE);
}
else if (rte->rtekind == RTE_SUBQUERY)
{
if (rte->lateral && root->hasJoinRTEs)
rte->subquery = (Query *)
flatten_join_alias_vars(root, (Node *) rte->subquery);
}
else if (rte->rtekind == RTE_FUNCTION)
{
kind = rte->lateral ? EXPRKIND_RTFUNC_LATERAL : EXPRKIND_RTFUNC;
rte->functions = (List *)
preprocess_expression(root, (Node *) rte->functions, kind);
}
else if (rte->rtekind == RTE_TABLEFUNC)
{
kind = rte->lateral ? EXPRKIND_TABLEFUNC_LATERAL : EXPRKIND_TABLEFUNC;
rte->tablefunc = (TableFunc *)
preprocess_expression(root, (Node *) rte->tablefunc, kind);
}
else if (rte->rtekind == RTE_VALUES)
{
kind = rte->lateral ? EXPRKIND_VALUES_LATERAL : EXPRKIND_VALUES;
rte->values_lists = (List *)
preprocess_expression(root, (Node *) rte->values_lists, kind);
}
foreach(lcsq, rte->securityQuals)
{
lfirst(lcsq) = preprocess_expression(root,
(Node *) lfirst(lcsq),
EXPRKIND_QUAL);
}
}
if (root->hasJoinRTEs)
{
foreach(l, parse->rtable)
{
RangeTblEntry *rte = lfirst_node(RangeTblEntry, l);
rte->joinaliasvars = NIL;
}
}
newHaving = NIL;
foreach(l, (List *) parse->havingQual)
{
Node *havingclause = (Node *) lfirst(l);
if ((parse->groupClause && parse->groupingSets) ||
contain_agg_clause(havingclause) ||
contain_volatile_functions(havingclause) ||
contain_subplans(havingclause))
{
newHaving = lappend(newHaving, havingclause);
}
else if (parse->groupClause && !parse->groupingSets)
{
parse->jointree->quals = (Node *)
lappend((List *) parse->jointree->quals, havingclause);
}
else
{
parse->jointree->quals = (Node *)
lappend((List *) parse->jointree->quals,
copyObject(havingclause));
newHaving = lappend(newHaving, havingclause);
}
}
parse->havingQual = (Node *) newHaving;
remove_useless_groupby_columns(root);
if (hasOuterJoins)
reduce_outer_joins(root);
if (parse->resultRelation &&
rt_fetch(parse->resultRelation, parse->rtable)->inh)
inheritance_planner(root);
else
grouping_planner(root, false, tuple_fraction);
SS_identify_outer_params(root);
final_rel = fetch_upper_rel(root, UPPERREL_FINAL, NULL);
SS_charge_for_initplans(root, final_rel);
set_cheapest(final_rel);
return root;
}3.create_plan
Plan *
create_plan(PlannerInfo *root, Path *best_path)
{
Plan *plan;
Assert(root->plan_params == NIL);
root->curOuterRels = NULL;
root->curOuterParams = NIL;
plan = create_plan_recurse(root, best_path, CP_EXACT_TLIST);
if (!IsA(plan, ModifyTable))
apply_tlist_labeling(plan->targetlist, root->processed_tlist);
SS_attach_initplans(root, plan);
if (root->curOuterParams != NIL)
elog(ERROR, "failed to assign all NestLoopParams to plan nodes");
root->plan_params = NIL;
return plan;
}
static Plan *
create_plan_recurse(PlannerInfo *root, Path *best_path, int flags)
{
Plan *plan;
check_stack_depth();
switch (best_path->pathtype)
{
case T_SeqScan:
case T_SampleScan:
case T_IndexScan:
case T_IndexOnlyScan:
case T_BitmapHeapScan:
case T_TidScan:
case T_SubqueryScan:
case T_FunctionScan:
case T_TableFuncScan:
case T_ValuesScan:
case T_CteScan:
case T_WorkTableScan:
case T_NamedTuplestoreScan:
case T_ForeignScan:
case T_CustomScan:
plan = create_scan_plan(root, best_path, flags);
break;
case T_HashJoin:
case T_MergeJoin:
case T_NestLoop:
plan = create_join_plan(root,
(JoinPath *) best_path);
break;
case T_Append:
plan = create_append_plan(root,
(AppendPath *) best_path);
break;
case T_MergeAppend:
plan = create_merge_append_plan(root,
(MergeAppendPath *) best_path);
break;
case T_Result:
if (IsA(best_path, ProjectionPath))
{
plan = create_projection_plan(root,
(ProjectionPath *) best_path,
flags);
}
else if (IsA(best_path, MinMaxAggPath))
{
plan = (Plan *) create_minmaxagg_plan(root,
(MinMaxAggPath *) best_path);
}
else
{
Assert(IsA(best_path, ResultPath));
plan = (Plan *) create_result_plan(root,
(ResultPath *) best_path);
}
break;
case T_ProjectSet:
plan = (Plan *) create_project_set_plan(root,
(ProjectSetPath *) best_path);
break;
case T_Material:
plan = (Plan *) create_material_plan(root,
(MaterialPath *) best_path,
flags);
break;
case T_Unique:
if (IsA(best_path, UpperUniquePath))
{
plan = (Plan *) create_upper_unique_plan(root,
(UpperUniquePath *) best_path,
flags);
}
else
{
Assert(IsA(best_path, UniquePath));
plan = create_unique_plan(root,
(UniquePath *) best_path,
flags);
}
break;
case T_Gather:
plan = (Plan *) create_gather_plan(root,
(GatherPath *) best_path);
break;
case T_Sort:
plan = (Plan *) create_sort_plan(root,
(SortPath *) best_path,
flags);
break;
case T_Group:
plan = (Plan *) create_group_plan(root,
(GroupPath *) best_path);
break;
case T_Agg:
if (IsA(best_path, GroupingSetsPath))
plan = create_groupingsets_plan(root,
(GroupingSetsPath *) best_path);
else
{
Assert(IsA(best_path, AggPath));
plan = (Plan *) create_agg_plan(root,
(AggPath *) best_path);
}
break;
case T_WindowAgg:
plan = (Plan *) create_windowagg_plan(root,
(WindowAggPath *) best_path);
break;
case T_SetOp:
plan = (Plan *) create_setop_plan(root,
(SetOpPath *) best_path,
flags);
break;
case T_RecursiveUnion:
plan = (Plan *) create_recursiveunion_plan(root,
(RecursiveUnionPath *) best_path);
break;
case T_LockRows:
plan = (Plan *) create_lockrows_plan(root,
(LockRowsPath *) best_path,
flags);
break;
case T_ModifyTable:
plan = (Plan *) create_modifytable_plan(root,
(ModifyTablePath *) best_path);
break;
case T_Limit:
plan = (Plan *) create_limit_plan(root,
(LimitPath *) best_path,
flags);
break;
case T_GatherMerge:
plan = (Plan *) create_gather_merge_plan(root,
(GatherMergePath *) best_path);
break;
default:
elog(ERROR, "unrecognized node type: %d",
(int) best_path->pathtype);
plan = NULL;
break;
}
return plan;
}
static ModifyTable *
create_modifytable_plan(PlannerInfo *root, ModifyTablePath *best_path)
{
ModifyTable *plan;
List *subplans = NIL;
ListCell *subpaths,
*subroots;
forboth(subpaths, best_path->subpaths,
subroots, best_path->subroots)
{
Path *subpath = (Path *) lfirst(subpaths);
PlannerInfo *subroot = (PlannerInfo *) lfirst(subroots);
Plan *subplan;
subplan = create_plan_recurse(subroot, subpath, CP_EXACT_TLIST);
apply_tlist_labeling(subplan->targetlist, subroot->processed_tlist);
subplans = lappend(subplans, subplan);
}
plan = make_modifytable(root,
best_path->operation,
best_path->canSetTag,
best_path->nominalRelation,
best_path->partitioned_rels,
best_path->partColsUpdated,
best_path->resultRelations,
subplans,
best_path->subroots,
best_path->withCheckOptionLists,
best_path->returningLists,
best_path->rowMarks,
best_path->onconflict,
best_path->epqParam);
copy_generic_path_info(&plan->plan, &best_path->path);
return plan;
}
static ModifyTable *
make_modifytable(PlannerInfo *root,
CmdType operation, bool canSetTag,
Index nominalRelation, List *partitioned_rels,
bool partColsUpdated,
List *resultRelations, List *subplans, List *subroots,
List *withCheckOptionLists, List *returningLists,
List *rowMarks, OnConflictExpr *onconflict, int epqParam)
{
ModifyTable *node = makeNode(ModifyTable);
List *fdw_private_list;
Bitmapset *direct_modify_plans;
ListCell *lc;
ListCell *lc2;
int i;
Assert(list_length(resultRelations) == list_length(subplans));
Assert(list_length(resultRelations) == list_length(subroots));
Assert(withCheckOptionLists == NIL ||
list_length(resultRelations) == list_length(withCheckOptionLists));
Assert(returningLists == NIL ||
list_length(resultRelations) == list_length(returningLists));
node->plan.lefttree = NULL;
node->plan.righttree = NULL;
node->plan.qual = NIL;
node->plan.targetlist = NIL;
node->operation = operation;
node->canSetTag = canSetTag;
node->nominalRelation = nominalRelation;
node->partitioned_rels = flatten_partitioned_rels(partitioned_rels);
node->partColsUpdated = partColsUpdated;
node->resultRelations = resultRelations;
node->resultRelIndex = -1;
node->rootResultRelIndex = -1;
node->plans = subplans;
if (!onconflict)
{
node->onConflictAction = ONCONFLICT_NONE;
node->onConflictSet = NIL;
node->onConflictWhere = NULL;
node->arbiterIndexes = NIL;
node->exclRelRTI = 0;
node->exclRelTlist = NIL;
}
else
{
node->onConflictAction = onconflict->action;
node->onConflictSet = onconflict->onConflictSet;
node->onConflictWhere = onconflict->onConflictWhere;
node->arbiterIndexes = infer_arbiter_indexes(root);
node->exclRelRTI = onconflict->exclRelIndex;
node->exclRelTlist = onconflict->exclRelTlist;
}
node->withCheckOptionLists = withCheckOptionLists;
node->returningLists = returningLists;
node->rowMarks = rowMarks;
node->epqParam = epqParam;
fdw_private_list = NIL;
direct_modify_plans = NULL;
i = 0;
forboth(lc, resultRelations, lc2, subroots)
{
Index rti = lfirst_int(lc);
PlannerInfo *subroot = lfirst_node(PlannerInfo, lc2);
FdwRoutine *fdwroutine;
List *fdw_private;
bool direct_modify;
if (rti < subroot->simple_rel_array_size &&
subroot->simple_rel_array[rti] != NULL)
{
RelOptInfo *resultRel = subroot->simple_rel_array[rti];
fdwroutine = resultRel->fdwroutine;
}
else
{
RangeTblEntry *rte = planner_rt_fetch(rti, subroot);
Assert(rte->rtekind == RTE_RELATION);
if (rte->relkind == RELKIND_FOREIGN_TABLE)
fdwroutine = GetFdwRoutineByRelId(rte->relid);
else
fdwroutine = NULL;
}
direct_modify = false;
if (fdwroutine != NULL &&
fdwroutine->PlanDirectModify != NULL &&
fdwroutine->BeginDirectModify != NULL &&
fdwroutine->IterateDirectModify != NULL &&
fdwroutine->EndDirectModify != NULL &&
withCheckOptionLists == NIL &&
!has_row_triggers(subroot, rti, operation))
direct_modify = fdwroutine->PlanDirectModify(subroot, node, rti, i);
if (direct_modify)
direct_modify_plans = bms_add_member(direct_modify_plans, i);
if (!direct_modify &&
fdwroutine != NULL &&
fdwroutine->PlanForeignModify != NULL)
fdw_private = fdwroutine->PlanForeignModify(subroot, node, rti, i);
else
fdw_private = NIL;
fdw_private_list = lappend(fdw_private_list, fdw_private);
i++;
}
node->fdwPrivLists = fdw_private_list;
node->fdwDirectModifyPlans = direct_modify_plans;
return node;
}三、跟踪分析
插入测试数据：
testdb=# insert into t_insert values(1000,'I am test','I am test','I am test');
(挂起)启动gdb，跟踪调试：
standard_planner
[root@localhost ~]# gdb -p 1610
GNU gdb (GDB) Red Hat Enterprise Linux 7.6.1-100.el7
Copyright (C) 2013 Free Software Foundation, Inc.
...
#跟踪进入subquery_planner(见后)
(gdb) n
409 final_rel = fetch_upper_rel(root, UPPERREL_FINAL, NULL);
(gdb)
410 best_path = get_cheapest_fractional_path(final_rel, tuple_fraction);
#最优路径,INSERT语句,Plan为T_ModifyTable
(gdb) p *best_path
$51 = {type = T_ModifyTablePath, pathtype = T_ModifyTable, parent = 0x21c40a0, pathtarget = 0x21c42b0,
param_info = 0x0, parallel_aware = false, parallel_safe = false, parallel_workers = 0, rows = 1,
startup_cost = 0, total_cost = 0.01, pathkeys = 0x0}
(gdb)
412 top_plan = create_plan(root, best_path);
(gdb) step
create_plan (root=0x21c2cb0, best_path=0x219dd88) at createplan.c:323
323 root->curOuterRels = NULL;
(gdb) n
324 root->curOuterParams = NIL;
(gdb)
327 plan = create_plan_recurse(root, best_path, CP_EXACT_TLIST);
(gdb)
336 if (!IsA(plan, ModifyTable))
#plan可用于后续的执行
(gdb) p *plan
$53 = {type = T_ModifyTable, startup_cost = 0, total_cost = 0.01, plan_rows = 1, plan_width = 298,
parallel_aware = false, parallel_safe = false, plan_node_id = 0, targetlist = 0x0, qual = 0x0,
lefttree = 0x0, righttree = 0x0, initPlan = 0x0, extParam = 0x0, allParam = 0x0}subquery_planner
[root@localhost ~]# gdb -p 1610
GNU gdb (GDB) Red Hat Enterprise Linux 7.6.1-100.el7
Copyright (C) 2013 Free Software Foundation, Inc.
...
(gdb) b subquery_planner
Breakpoint 1 at 0x76a0bb: file planner.c, line 606.
(gdb) c
Continuing.
...
Breakpoint 1, subquery_planner (glob=0x21c2c20, parse=0x219de98, parent_root=0x0, hasRecursion=false,
tuple_fraction=0) at planner.c:606
606 root = makeNode(PlannerInfo);
#输入参数
#1,glob
(gdb) p *glob
$1 = {type = T_PlannerGlobal, boundParams = 0x0, subplans = 0x0, subroots = 0x0, rewindPlanIDs = 0x0,
finalrtable = 0x0, finalrowmarks = 0x0, resultRelations = 0x0, nonleafResultRelations = 0x0,
rootResultRelations = 0x0, relationOids = 0x0, invalItems = 0x0, paramExecTypes = 0x0, lastPHId = 0,
lastRowMarkId = 0, lastPlanNodeId = 0, transientPlan = false, dependsOnRole = false,
parallelModeOK = false, parallelModeNeeded = false, maxParallelHazard = 117 'u'}
#2,parse
#Query结构体
(gdb) p *parse
$2 = {type = T_Query, commandType = CMD_INSERT, querySource = QSRC_ORIGINAL, queryId = 0, canSetTag = true,
utilityStmt = 0x0, resultRelation = 1, hasAggs = false, hasWindowFuncs = false, hasTargetSRFs = false,
hasSubLinks = false, hasDistinctOn = false, hasRecursive = false, hasModifyingCTE = false,
hasForUpdate = false, hasRowSecurity = false, cteList = 0x0, rtable = 0x219e2b8, jointree = 0x21c2aa0,
targetList = 0x21c2b20, override = OVERRIDING_NOT_SET, onConflict = 0x0, returningList = 0x0,
groupClause = 0x0, groupingSets = 0x0, havingQual = 0x0, windowClause = 0x0, distinctClause = 0x0,
sortClause = 0x0, limitOffset = 0x0, limitCount = 0x0, rowMarks = 0x0, setOperations = 0x0,
constraintDeps = 0x0, withCheckOptions = 0x0, stmt_location = 0, stmt_len = 69}
#targetList中的元素为TargetEntry *
#在insert语句中,是数据表列
(gdb) p *(parse->targetList)
$3 = {type = T_List, length = 4, head = 0x21c2b00, tail = 0x21c2b90}
(gdb) p *((TargetEntry *)(parse->targetList->head->data.ptr_value))
$4 = {xpr = {type = T_TargetEntry}, expr = 0x219e5e8, resno = 1, resname = 0x219e338 "id",
ressortgroupref = 0, resorigtbl = 0, resorigcol = 0, resjunk = false}
#rtable中的元素是RangeTblEntry *
#在insert操作中,是数据表
(gdb) p *(parse->rtable)
$5 = {type = T_List, length = 1, head = 0x219e298, tail = 0x219e298}
(gdb) p *((RangeTblEntry *)(parse->rtable->head->data.ptr_value))
$6 = {type = T_RangeTblEntry, rtekind = RTE_RELATION, relid = 26731, relkind = 114 'r', tablesample = 0x0,
subquery = 0x0, security_barrier = false, jointype = JOIN_INNER, joinaliasvars = 0x0, functions = 0x0,
funcordinality = false, tablefunc = 0x0, values_lists = 0x0, ctename = 0x0, ctelevelsup = 0,
self_reference = false, coltypes = 0x0, coltypmods = 0x0, colcollations = 0x0, enrname = 0x0,
enrtuples = 0, alias = 0x0, eref = 0x219e0b8, lateral = false, inh = false, inFromCl = false,
requiredPerms = 1, checkAsUser = 0, selectedCols = 0x0, insertedCols = 0x21c2938, updatedCols = 0x0,
securityQuals = 0x0}
(gdb) p *(((RangeTblEntry *)(parse->rtable->head->data.ptr_value))->insertedCols)
$7 = {nwords = 1, words = 0x21c293c}
#3,parent_root
(gdb) p *parent_root
Cannot access memory at address 0x0
#4,hasRecursion
(gdb) p hasRecursion
$9 = false
#5,tuple_fraction
(gdb) p tuple_fraction
$10 = 0
...
639 if (parse->cteList)
(gdb)
648 if (parse->hasSubLinks)
(gdb)
656 inline_set_returning_functions(root);
(gdb)
662 pull_up_subqueries(root);
(gdb)
670 if (parse->setOperations)
(gdb)
680 root->hasJoinRTEs = false;
(gdb)
681 root->hasLateralRTEs = false;
682 hasOuterJoins = false;
(gdb)
683 foreach(l, parse->rtable)
(gdb)
685 RangeTblEntry *rte = lfirst_node(RangeTblEntry, l);
(gdb)
687 if (rte->rtekind == RTE_JOIN)
(gdb) p *rte
$11 = {type = T_RangeTblEntry, rtekind = RTE_RELATION, relid = 26731, relkind = 114 'r', tablesample = 0x0,
subquery = 0x0, security_barrier = false, jointype = JOIN_INNER, joinaliasvars = 0x0, functions = 0x0,
funcordinality = false, tablefunc = 0x0, values_lists = 0x0, ctename = 0x0, ctelevelsup = 0,
self_reference = false, coltypes = 0x0, coltypmods = 0x0, colcollations = 0x0, enrname = 0x0,
enrtuples = 0, alias = 0x0, eref = 0x219e0b8, lateral = false, inh = false, inFromCl = false,
requiredPerms = 1, checkAsUser = 0, selectedCols = 0x0, insertedCols = 0x21c2938, updatedCols = 0x0,
securityQuals = 0x0}
...
731 parse->targetList = (List *)
(gdb)
736 if (parse->hasTargetSRFs)
(gdb) p *((TargetEntry *)(parse->targetList->head->data.ptr_value))
$12 = {xpr = {type = T_TargetEntry}, expr = 0x21c3110, resno = 1, resname = 0x219e338 "id",
ressortgroupref = 0, resorigtbl = 0, resorigcol = 0, resjunk = false}
(gdb) p *(((TargetEntry *)(parse->targetList->head->data.ptr_value))->expr)
$13 = {type = T_Const}
...
#进入grouping_planner函数,此函数生成root->upper_rels & upper_targets
#注意upper_rels,grouping_planner函数执行完毕,upper_rels最后一个元素会填入相应的值
(gdb) p *root
$22 = {type = T_PlannerInfo, parse = 0x219de98, glob = 0x21c2c20, query_level = 1, parent_root = 0x0,
plan_params = 0x0, outer_params = 0x0, simple_rel_array = 0x0, simple_rel_array_size = 0,
simple_rte_array = 0x0, all_baserels = 0x0, nullable_baserels = 0x0, join_rel_list = 0x0,
join_rel_hash = 0x0, join_rel_level = 0x0, join_cur_level = 0, init_plans = 0x0, cte_plan_ids = 0x0,
multiexpr_params = 0x0, eq_classes = 0x0, canon_pathkeys = 0x0, left_join_clauses = 0x0,
right_join_clauses = 0x0, full_join_clauses = 0x0, join_info_list = 0x0, append_rel_list = 0x0,
rowMarks = 0x0, placeholder_list = 0x0, fkey_list = 0x0, query_pathkeys = 0x0, group_pathkeys = 0x0,
window_pathkeys = 0x0, distinct_pathkeys = 0x0, sort_pathkeys = 0x0, part_schemes = 0x0,
initial_rels = 0x0, upper_rels = {0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0}, upper_targets = {0x0, 0x0, 0x0, 0x0,
0x0, 0x0, 0x0}, processed_tlist = 0x0, grouping_map = 0x0, minmax_aggs = 0x0, planner_cxt = 0x219cde0,
total_table_pages = 0, tuple_fraction = 0, limit_tuples = 0, qual_security_level = 0,
inhTargetKind = INHKIND_NONE, hasJoinRTEs = false, hasLateralRTEs = false, hasDeletedRTEs = false,
hasHavingQual = false, hasPseudoConstantQuals = false, hasRecursion = false, wt_param_id = -1,
non_recursive_path = 0x0, curOuterRels = 0x0, curOuterParams = 0x0, join_search_private = 0x0,
partColsUpdated = false}
(gdb) p inheritance_update
$23 = false
(gdb) p inheritance_update
$24 = false
(gdb) p tuple_fraction
$25 = 0
(gdb)
...
(gdb)
1808 tlist = preprocess_targetlist(root);
(gdb) p *root
$27 = {type = T_PlannerInfo, parse = 0x219de98, glob = 0x21c2c20, query_level = 1, parent_root = 0x0,
plan_params = 0x0, outer_params = 0x0, simple_rel_array = 0x0, simple_rel_array_size = 0,
simple_rte_array = 0x0, all_baserels = 0x0, nullable_baserels = 0x0, join_rel_list = 0x0,
join_rel_hash = 0x0, join_rel_level = 0x0, join_cur_level = 0, init_plans = 0x0, cte_plan_ids = 0x0,
multiexpr_params = 0x0, eq_classes = 0x0, canon_pathkeys = 0x0, left_join_clauses = 0x0,
right_join_clauses = 0x0, full_join_clauses = 0x0, join_info_list = 0x0, append_rel_list = 0x0,
rowMarks = 0x0, placeholder_list = 0x0, fkey_list = 0x0, query_pathkeys = 0x0, group_pathkeys = 0x0,
window_pathkeys = 0x0, distinct_pathkeys = 0x0, sort_pathkeys = 0x0, part_schemes = 0x0,
initial_rels = 0x0, upper_rels = {0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0}, upper_targets = {0x0, 0x0, 0x0, 0x0,
0x0, 0x0, 0x0}, processed_tlist = 0x21c39e0, grouping_map = 0x0, minmax_aggs = 0x0,
planner_cxt = 0x219cde0, total_table_pages = 0, tuple_fraction = 0, limit_tuples = 0,
qual_security_level = 0, inhTargetKind = INHKIND_NONE, hasJoinRTEs = false, hasLateralRTEs = false,
hasDeletedRTEs = false, hasHavingQual = false, hasPseudoConstantQuals = false, hasRecursion = false,
wt_param_id = -1, non_recursive_path = 0x0, curOuterRels = 0x0, curOuterParams = 0x0,
join_search_private = 0x0, partColsUpdated = false}
#processed_tlist中的元素为TargetEntry *,也就是字段Column
(gdb) p *(root->processed_tlist)
$28 = {type = T_List, length = 4, head = 0x21c39c0, tail = 0x21c3a50}
(gdb) p *(root->processed_tlist->head)
$29 = {data = {ptr_value = 0x21c30c0, int_value = 35401920, oid_value = 35401920}, next = 0x21c3a10}
(gdb) p *(TargetEntry *)(root->processed_tlist->head.data->ptr_value)
$30 = {xpr = {type = T_TargetEntry}, expr = 0x21c3110, resno = 1, resname = 0x219e338 "id",
ressortgroupref = 0, resorigtbl = 0, resorigcol = 0, resjunk = false}
...
2026 root->upper_targets[UPPERREL_FINAL] = final_target;
(gdb)
2027 root->upper_targets[UPPERREL_WINDOW] = sort_input_target;
(gdb)
2028 root->upper_targets[UPPERREL_GROUP_AGG] = grouping_target;
(gdb)
2035 if (have_grouping)
(gdb) p *final_target
$45 = {type = T_PathTarget, exprs = 0x21c3ee0, sortgrouprefs = 0x21c3ea0, cost = {startup = 0,
...
(gdb)
2197 create_modifytable_path(root, final_rel,
(gdb)
2200 parse->resultRelation,
(gdb) p *root
$49 = {type = T_PlannerInfo, parse = 0x219de98, glob = 0x21c2c20, query_level = 1, parent_root = 0x0,
plan_params = 0x0, outer_params = 0x0, simple_rel_array = 0x0, simple_rel_array_size = 0,
simple_rte_array = 0x0, all_baserels = 0x0, nullable_baserels = 0x0, join_rel_list = 0x21c3cf0,
join_rel_hash = 0x0, join_rel_level = 0x0, join_cur_level = 0, init_plans = 0x0, cte_plan_ids = 0x0,
multiexpr_params = 0x0, eq_classes = 0x0, canon_pathkeys = 0x0, left_join_clauses = 0x0,
right_join_clauses = 0x0, full_join_clauses = 0x0, join_info_list = 0x0, append_rel_list = 0x0,
rowMarks = 0x0, placeholder_list = 0x0, fkey_list = 0x0, query_pathkeys = 0x0, group_pathkeys = 0x0,
window_pathkeys = 0x0, distinct_pathkeys = 0x0, sort_pathkeys = 0x0, part_schemes = 0x0,
initial_rels = 0x0, upper_rels = {0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x21c4320}, upper_targets = {0x0, 0x0,
0x21c3e50, 0x21c3e50, 0x0, 0x0, 0x21c3e50}, processed_tlist = 0x21c39e0, grouping_map = 0x0,
minmax_aggs = 0x0, planner_cxt = 0x219cde0, total_table_pages = 0, tuple_fraction = 0, limit_tuples = -1,
qual_security_level = 0, inhTargetKind = INHKIND_NONE, hasJoinRTEs = false, hasLateralRTEs = false,
hasDeletedRTEs = false, hasHavingQual = false, hasPseudoConstantQuals = false, hasRecursion = false,
wt_param_id = -1, non_recursive_path = 0x0, curOuterRels = 0x0, curOuterParams = 0x0,
join_search_private = 0x0, partColsUpdated = false}
(gdb) finish
Run till exit from #0 grouping_planner (root=0x21c2cb0, inheritance_update=false, tuple_fraction=0)
at planner.c:2200
subquery_planner (glob=0x21c2c20, parse=0x219de98, parent_root=0x0, hasRecursion=false, tuple_fraction=0)
at planner.c:972
#退出grouping_planner函数
...
#最终的返回值
#INSERT VALUES语句相对比较简单,没有复杂的JOIN/WITH/HAVING/GROUP等语句,这里只是简单的返回一个root节点
(gdb) p *root
$17 = {type = T_PlannerInfo, parse = 0x219de98, glob = 0x21c2c20, query_level = 1, parent_root = 0x0,
plan_params = 0x0, outer_params = 0x0, simple_rel_array = 0x0, simple_rel_array_size = 0,
simple_rte_array = 0x0, all_baserels = 0x0, nullable_baserels = 0x0, join_rel_list = 0x21c3cf0,
join_rel_hash = 0x0, join_rel_level = 0x0, join_cur_level = 0, init_plans = 0x0, cte_plan_ids = 0x0,
multiexpr_params = 0x0, eq_classes = 0x0, canon_pathkeys = 0x0, left_join_clauses = 0x0,
right_join_clauses = 0x0, full_join_clauses = 0x0, join_info_list = 0x0, append_rel_list = 0x0,
rowMarks = 0x0, placeholder_list = 0x0, fkey_list = 0x0, query_pathkeys = 0x0, group_pathkeys = 0x0,
window_pathkeys = 0x0, distinct_pathkeys = 0x0, sort_pathkeys = 0x0, part_schemes = 0x0,
initial_rels = 0x0, upper_rels = {0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x21c4320}, upper_targets = {0x0, 0x0,
0x21c3e50, 0x21c3e50, 0x0, 0x0, 0x21c3e50}, processed_tlist = 0x21c39e0, grouping_map = 0x0,
minmax_aggs = 0x0, planner_cxt = 0x219cde0, total_table_pages = 0, tuple_fraction = 0, limit_tuples = -1,
qual_security_level = 0, inhTargetKind = INHKIND_NONE, hasJoinRTEs = false, hasLateralRTEs = false,
hasDeletedRTEs = false, hasHavingQual = false, hasPseudoConstantQuals = false, hasRecursion = false,
wt_param_id = -1, non_recursive_path = 0x0, curOuterRels = 0x0, curOuterParams = 0x0,
join_search_private = 0x0, partColsUpdated = false}四、小结
1.重要的数据结构:PlannedStmt/PlannerGlobal/PlannerInfo/RelOptInfo/Path
2.重要的函数:subquery_planner/grouping_planner/create_plan
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