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Code Issues

Fixed CORE-5366 - Regression: could not use CASE expression with more than 255 conditions.

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Adriano dos Santos Fernandes 2016-10-07 09:35:53 -03:00
parent b388b0effc
commit 300fb11e43
1 changed files with 53 additions and 0 deletions
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53
src/dsql/ExprNodes.cpp
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@ -3807,6 +3807,59 @@ ValueExprNode* DecodeNode::dsqlPass(DsqlCompilerScratch* dsqlScratch)
node->label = label;
node->make(dsqlScratch, &node->nodDesc); // Set descriptor for output node.
node->setParameterType(dsqlScratch, &node->nodDesc, false);
// Workaround for DECODE/CASE supporting only 255 items - see CORE-5366.
const static unsigned MAX_COUNT = 254;
if (node->values->items.getCount() > MAX_COUNT)
{
NestValueArray conditions(node->conditions->items.getCount() - MAX_COUNT);
conditions.push(node->conditions->items.begin() + MAX_COUNT, conditions.getCapacity());
node->conditions->items.shrink(MAX_COUNT);
NestValueArray values(node->values->items.getCount() - MAX_COUNT);
values.push(node->values->items.begin() + MAX_COUNT, values.getCapacity());
node->values->items.shrink(MAX_COUNT + 1);
DecodeNode* innerNode = node;
bool hasElse = values.getCount() != conditions.getCount();
unsigned index = 0;
bool last;
do
{
unsigned count = conditions.getCount() - index;
last = count <= MAX_COUNT;
unsigned valuesCount = MIN(MAX_COUNT, count) + (last && hasElse ? 1 : 0);
unsigned conditionsCount = MIN(MAX_COUNT, count);
if (last && conditionsCount == 0)
{
fb_assert(valuesCount == 1);
innerNode->values->items.back() = values[index];
}
else
{
DecodeNode* newNode = FB_NEW_POOL(getPool()) DecodeNode(getPool(),
doDsqlPass(dsqlScratch, test),
FB_NEW_POOL(getPool()) ValueListNode(getPool(), conditionsCount),
FB_NEW_POOL(getPool()) ValueListNode(getPool(), valuesCount + (last ? 0 : 1)));
newNode->conditions->items.assign(conditions.begin() + index, conditionsCount);
newNode->values->items.assign(values.begin() + index, valuesCount);
if (!last)
newNode->values->items.push(NULL);
innerNode->values->items.back() = newNode;
innerNode = newNode;
index += conditionsCount;
}
} while (!last);
}
return node;
}