Github user navsan commented on a diff in the pull request:
https://github.com/apache/incubator-quickstep/pull/100#discussion_r79695417
--- Diff: storage/SplitRowStoreTupleStorageSubBlock.cpp ---
@@ -88,6 +88,67 @@ inline std::size_t
CalculateVariableSizeWithRemappedAttributes(
return total_size;
}
+
+/**
+ * A struct which holds the offset information for a non-remapping insert
+ * operation
+ */
+struct BasicInsertInfo {
+ BasicInsertInfo(
+ const CatalogRelationSchema &relation)
+ : num_attrs_(relation.size()),
+ num_nullable_attrs_(relation.numNullableAttributes()),
+ max_var_length_(relation.getMaximumVariableByteLength()),
+ fixed_len_offset_(BitVector<true>::BytesNeeded(num_nullable_attrs_)),
+ var_len_offset_(fixed_len_offset_ + relation.getFixedByteLength()),
+ is_variable_(num_attrs_),
+ is_nullable_(num_attrs_),
+ fixed_len_offsets_(num_attrs_),
+ fixed_len_sizes_(num_attrs_),
+ var_len_offsets_(num_attrs_) {
+ attribute_id accessor_attr_id = 0;
+ for (CatalogRelationSchema::const_iterator attr_it = relation.begin();
+ attr_it != relation.end();
+ ++attr_it, ++accessor_attr_id) {
+ DCHECK_EQ(accessor_attr_id, attr_it->getID());
+
+ const int nullable_idx =
relation.getNullableAttributeIndex(accessor_attr_id);
+ const int variable_idx =
relation.getVariableLengthAttributeIndex(accessor_attr_id);
+ is_nullable_.setBit(accessor_attr_id, nullable_idx != -1);
+
+ if (variable_idx == -1) {
+ is_variable_.setBit(accessor_attr_id, false);
+ fixed_len_offsets_[accessor_attr_id] =
relation.getFixedLengthAttributeOffset(accessor_attr_id);
+ fixed_len_sizes_[accessor_attr_id] = relation.getAttributeById(
+ accessor_attr_id)->getType().maximumByteLength();
+ var_len_offsets_[accessor_attr_id] = -1;
+ } else {
+ is_variable_.setBit(accessor_attr_id, true);
+ fixed_len_offsets_[accessor_attr_id] = 0;
+ fixed_len_sizes_[accessor_attr_id] = 0;
+ var_len_offsets_[accessor_attr_id] =
relation.getVariableLengthAttributeIndex(accessor_attr_id);
+ }
+ }
+ }
+
+ std::size_t num_attrs_;
+ std::size_t num_nullable_attrs_;
+ std::size_t max_var_length_;
+
+ // byte offset from the beginning of a tuple to the first fixed length
attribute
+ std::uint32_t fixed_len_offset_;
+ // byte offset from the beginning of a tuple to the first variable
length offset/length pair
+ std::uint32_t var_len_offset_;
+
+ BitVector<true> is_variable_;
--- End diff --
Packing these Booleans into a bitvector is needlessly expensive. Just use
straight up 1-byte bools instead. We only have a few columns, so the space
overhead is negligible. But doing so will avoid the complexity/cost of bit
arithmetic to do lookups during insertion.
[This applies to both the bitmaps.]
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