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Rework my fix for #5654: Could not execute query (select from view with nested view) -- the original solution was too restrictive, causing regressions in plans/performance

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Dmitry Yemanov 2024-11-07 12:49:17 +03:00
parent b0c36f09af
commit 79583d675b
1 changed files with 8 additions and 7 deletions
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15
src/jrd/optimizer/Optimizer.cpp
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@ -1971,14 +1971,15 @@ void Optimizer::checkSorts()
unsigned Optimizer::distributeEqualities(BoolExprNodeStack& orgStack, unsigned baseCount)
{
// dimitr: Dumb protection against too many injected conjuncts (see CORE-5381).
// Don't produce more additional conjuncts than we originally had
// (i.e. this routine should never more than double the number of conjuncts).
// Ideally, we need two separate limits here:
// 1) number of injected conjuncts (affects required impure size)
// 2) number of input conjuncts (affects search time inside this routine)
// dimitr: Simplified protection against too many injected conjuncts (see CORE-5381).
// Two separate limits are applied here:
// 1) number of input conjuncts (affects search time inside this routine)
// 2) number of injected conjuncts (affects required impure size)
if (baseCount * 2 > MAX_CONJUNCTS)
constexpr unsigned MAX_CONJUNCTS_TO_PROCESS = 1024;
const unsigned MAX_CONJUNCTS_TO_INJECT = MAX(baseCount, 256);
if (baseCount > MAX_CONJUNCTS_TO_PROCESS)
return 0;
ObjectsArray<ValueExprNodeStack> classes;