/**
* Is a result node memory intensive? It is if it contains function calls.
* We special-case certain functions used by ORCA which we know that are not
* memory intensive
* TODO caragg 03/04/2014: Revert these changes when ORCA has the new partition
* operator (MPP-22799)
*/
bool
IsResultMemoryIntesive(Result *res)
{
List *funcNodes = extract_nodes(NULL /* glob */,
(Node *) ((Plan *) res)->targetlist, T_FuncExpr);
int nFuncExpr = list_length(funcNodes);
if (nFuncExpr == 0)
{
/* No function expressions, not memory intensive */
return false;
}
bool isMemoryIntensive = false;
ListCell *lc = NULL;
foreach(lc, funcNodes)
{
FuncExpr *funcExpr = lfirst(lc);
Assert(IsA(funcExpr, FuncExpr));
if ( isMemoryIntensiveFunction(funcExpr->funcid))
{
/* Found a function that we don't know of. Mark as memory intensive */
isMemoryIntensive = true;
break;
}
}
/**
* This method looks at the Append part of the plan under a join and extracts out interesting bits of information.
* These include: partitionOid of the master table, partitionInfo that is a struct containing partitioning information,
* what are the partitioning keys and what does an all null row of the partitioned table look like.
*/
static void MatchAppendPattern(Plan *append, PartitionJoinMutatorContext *ctx)
{
ctx->partitionOid = InvalidOid;
/**
* It is possible we have already applied the transformation to this subtree.
* Check for result node as child.
*/
Append *appendNode = (Append *) append;
Assert(list_length(appendNode->appendplans) > 0);
Plan *child = (Plan *) list_nth(appendNode->appendplans, 0);
if (IsA(child, Result))
{
ctx->safeToConvert = false;
return;
}
/**
* Find all the vars in the targetlist and check if they're from a partitioned table.
*/
List *allVars = extract_nodes(NULL /* PlannerGlobal */, (Node *) append->targetlist, T_Var);
ListCell *lc = NULL;
foreach (lc, allVars)
{
Var *v = (Var *) lfirst(lc);
RangeTblEntry *rte = rt_fetch(v->varno, ctx->rtable);
Assert(rte);
if (!rel_is_partitioned(rte->relid))
{
ctx->safeToConvert = false;
return;
}
if (ctx->partitionOid == InvalidOid)
{
ctx->partitionOid = rte->relid;
ctx->partitionVarno = v->varno;
}
if (ctx->partitionOid != rte->relid)
{
ctx->safeToConvert = false;
return;
}
}
