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add paths for joins instead of rewriting them

moonshot/custom-path
Nils Dijk 2020-05-07 19:01:39 +02:00
parent 84068f79b2
commit 23b11b470b
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GPG Key ID: CA1177EF9434F241
1 changed files with 24 additions and 10 deletions
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34
src/backend/distributed/planner/path_based_planner.c
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@ -18,6 +18,7 @@
#include "nodes/pathnodes.h"
#include "nodes/pg_list.h"
#include "nodes/plannodes.h"
#include "optimizer/pathnode.h"
#include "optimizer/restrictinfo.h"
static Plan * CreateDistributedUnionPlan(PlannerInfo *root, RelOptInfo *rel, struct CustomPath *best_path, List *tlist, List *clauses, List *custom_plans);
@ -26,7 +27,7 @@ static CustomPath * WrapTableAccessWithDistributedUnion(Path *originalPath, uint
static Query * GetQueryFromPath(PlannerInfo *root, Path *path, List *tlist, List *clauses);
static List * ShardIntervalListToRelationShardList(List *shardIntervalList);
static Path * OptimizeJoinPath(Path *originalPath);
static bool CanOptimizeJoinPath(JoinPath *jpath);
static bool CanOptimizeJoinPath(const JoinPath *jpath);
static bool IsDistributedUnion(Path *path);
static Expr * ExtractPartitionValue(List *restrictionList, Var *partitionKey);
static List * ShardIntervalListForRelationPartitionValue(Oid relationId, Expr *partitionValue);
@ -300,7 +301,7 @@ ExtractPartitionValue(List *restrictionList, Var *partitionKey)
static bool
CanOptimizeJoinPath(JoinPath *jpath)
CanOptimizeJoinPath(const JoinPath *jpath)
{
if (!(IsDistributedUnion(jpath->innerjoinpath) &&
IsDistributedUnion(jpath->outerjoinpath)))
@ -336,21 +337,30 @@ OptimizeJoinPath(Path *originalPath)
case T_NestLoop:
case T_HashJoin:
{
JoinPath *jpath = (JoinPath *) originalPath;
const JoinPath *jpath = (JoinPath *) originalPath;
if (CanOptimizeJoinPath(jpath))
{
/* we can only optimize the Distributed union if the colocationId's are the same, taking any would suffice */
DistributedUnionPath *baseDistUnion = (DistributedUnionPath *) jpath->innerjoinpath;
jpath->innerjoinpath = ((DistributedUnionPath *) jpath->innerjoinpath)->worker_path;
jpath->outerjoinpath = ((DistributedUnionPath *) jpath->outerjoinpath)->worker_path;
/*
* Shallow copy of any join node, this does not imply executing a nested
* join, but the nested join contains all the information we need to send
* the join to the worker
*/
JoinPath *jcpath = makeNode(NestPath);
*jcpath = *jpath;
jcpath->path.type = T_NestPath;
jcpath->innerjoinpath = ((DistributedUnionPath *) jpath->innerjoinpath)->worker_path;
jcpath->outerjoinpath = ((DistributedUnionPath *) jpath->outerjoinpath)->worker_path;
/* TODO update costs of hashjoin, very naife removal of DU cost for now */
jpath->path.startup_cost -= 2000; /* remove the double dist union cost */
jpath->path.total_cost -= 2000; /* remove the double dist union cost */
jcpath->path.startup_cost -= 2000; /* remove the double dist union cost */
jcpath->path.total_cost -= 2000; /* remove the double dist union cost */
return (Path *) WrapTableAccessWithDistributedUnion(
(Path *) jpath,
(Path *) jcpath,
baseDistUnion->colocationId,
baseDistUnion->partitionValue,
baseDistUnion->sampleRelid);
@ -359,7 +369,7 @@ OptimizeJoinPath(Path *originalPath)
default:
{
return originalPath;
return NULL;
}
}
}
@ -379,7 +389,11 @@ PathBasedPlannerJoinHook(PlannerInfo *root,
foreach(pathCell, joinrel->pathlist)
{
Path *originalPath = lfirst(pathCell);
pathCell->data.ptr_value = OptimizeJoinPath(originalPath);
Path *optimizedPath = OptimizeJoinPath(originalPath);
if (optimizedPath)
{
add_path(joinrel, optimizedPath);
}
}
}
}