int main(int argc, char** argv)
{
cout << string(SPLITTER_LEN, '=') << endl;
chooseMethod();
return 0;
}
void Join::setSampleBlock(const Block & block)
{
std::unique_lock lock(rwlock);
if (!empty())
return;
size_t keys_size = key_names_right.size();
ColumnRawPtrs key_columns(keys_size);
Columns materialized_columns(keys_size);
for (size_t i = 0; i < keys_size; ++i)
{
materialized_columns[i] = recursiveRemoveLowCardinality(block.getByName(key_names_right[i]).column);
key_columns[i] = materialized_columns[i].get();
/// We will join only keys, where all components are not NULL.
if (key_columns[i]->isColumnNullable())
key_columns[i] = &static_cast<const ColumnNullable &>(*key_columns[i]).getNestedColumn();
}
/// Choose data structure to use for JOIN.
init(chooseMethod(key_columns, key_sizes));
sample_block_with_columns_to_add = materializeBlock(block);
/// Move from `sample_block_with_columns_to_add` key columns to `sample_block_with_keys`, keeping the order.
size_t pos = 0;
while (pos < sample_block_with_columns_to_add.columns())
{
const auto & name = sample_block_with_columns_to_add.getByPosition(pos).name;
if (key_names_right.end() != std::find(key_names_right.begin(), key_names_right.end(), name))
{
auto & col = sample_block_with_columns_to_add.getByPosition(pos);
col.column = recursiveRemoveLowCardinality(col.column);
col.type = recursiveRemoveLowCardinality(col.type);
sample_block_with_keys.insert(col);
sample_block_with_columns_to_add.erase(pos);
}
else
++pos;
}
size_t num_columns_to_add = sample_block_with_columns_to_add.columns();
for (size_t i = 0; i < num_columns_to_add; ++i)
{
auto & column = sample_block_with_columns_to_add.getByPosition(i);
if (!column.column)
column.column = column.type->createColumn();
}
/// In case of LEFT and FULL joins, if use_nulls, convert joined columns to Nullable.
if (use_nulls && (kind == ASTTableJoin::Kind::Left || kind == ASTTableJoin::Kind::Full))
for (size_t i = 0; i < num_columns_to_add; ++i)
convertColumnToNullable(sample_block_with_columns_to_add.getByPosition(i));
}
