/* * Copyright (C) 2019-present ScyllaDB * * Modified by ScyllaDB */ /* * SPDX-License-Identifier: (LicenseRef-ScyllaDB-Source-Available-1.0 and Apache-2.0) */ #include "mutation/mutation.hh" #include "modification_statement.hh" #include "cas_request.hh" #include #include "cql3/result_set.hh" #include "cql3/expr/evaluate.hh" #include "cql3/expr/expr-utils.hh" #include "transport/messages/result_message.hh" #include "types/map.hh" #include "service/storage_proxy.hh" #include "cql3/query_processor.hh" namespace cql3::statements { using namespace std::chrono; void cas_request::add_row_update(const modification_statement& stmt_arg, std::vector ranges_arg, modification_statement::json_cache_opt json_cache_arg, const query_options& options_arg) { // TODO: reserve updates array for batches _updates.emplace_back(cas_row_update{ .statement = stmt_arg, .ranges = std::move(ranges_arg), .json_cache = std::move(json_cache_arg), .options = options_arg}); } std::optional cas_request::apply_updates(api::timestamp_type ts) const { // We're working with a single partition, so there will be only one element // in the vector. A vector is used since this is a conventional format // to pass a mutation onward. std::optional mutation_set; for (const cas_row_update& op: _updates) { update_parameters params(_schema, op.options, ts, op.statement.get_time_to_live(op.options), _rows); auto statement_mutations = op.statement.apply_updates(_key, op.ranges, params, op.json_cache); // Append all mutations (in fact only one) to the consolidated one. for (mutation& m : statement_mutations) { if (mutation_set.has_value() == false) { mutation_set.emplace(std::move(m)); } else { mutation_set->apply(std::move(m)); } } } return mutation_set; } lw_shared_ptr cas_request::read_command(query_processor& qp) const { column_set columns_to_read(_schema->all_columns_count()); std::vector ranges; for (const cas_row_update& op : _updates) { if (op.statement.has_conditions() == false && op.statement.requires_read() == false) { // No point in pre-fetching the old row if the statement doesn't check it in a CAS and // doesn't use it to apply updates. continue; } columns_to_read.union_with(op.statement.columns_to_read()); if (op.statement.has_only_static_column_conditions() && !op.statement.requires_read()) { // If a statement has only static column conditions and doesn't have operations that // require read, it doesn't matter what clustering key range to query - any partition // row will do for the check. continue; } ranges.reserve(op.ranges.size()); std::copy(op.ranges.begin(), op.ranges.end(), std::back_inserter(ranges)); } uint64_t max_rows = query::partition_max_rows; if (ranges.empty()) { // With only a static condition, we still want to make the distinction between // a non-existing partition and one that exists (has some live data) but has not // static content. So we query the first live row of the partition. ranges.emplace_back(query::clustering_range::make_open_ended_both_sides()); max_rows = 1; } else { // WARNING: clustering_range::deoverlap can return incorrect results - refer to scylladb#22817 and scylladb#21604 ranges = query::clustering_range::deoverlap(std::move(ranges), clustering_key::tri_compare(*_schema)); } auto options = update_parameters::options; options.set(query::partition_slice::option::always_return_static_content); query::partition_slice ps(std::move(ranges), *_schema, columns_to_read, options); ps.set_partition_row_limit(max_rows); return make_lw_shared(_schema->id(), _schema->version(), std::move(ps), qp.proxy().get_max_result_size(ps), query::tombstone_limit(qp.proxy().get_tombstone_limit())); } bool cas_request::applies_to() const { for (const cas_row_update& op: _updates) { if (!op.statement.has_conditions()) { continue; } // No need to check subsequent conditions as we have already failed the current one. auto old_row = find_old_row(op).row; if (!op.statement.applies_to(_rows.selection.get(), old_row, op.options)) { return false; } } return true; } std::optional cas_request::apply(foreign_ptr> qr, const query::partition_slice& slice, api::timestamp_type ts, cdc::per_request_options&) { _rows = update_parameters::build_prefetch_data(_schema, *qr, slice); if (applies_to()) { return apply_updates(ts); } else { return {}; } } cas_request::old_row cas_request::find_old_row(const cas_row_update& op) const { static const clustering_key empty_ckey = clustering_key::make_empty(); if (_key.empty()) { throw exceptions::invalid_request_exception("Empty partition key range"); } const partition_key& pkey = _key.front().start()->value().key().value(); // We must ignore statement clustering column restriction when // choosing a row to check the conditions. If there is no // exact match, choose static row to check if the statement // applies. // For example, the following update must successfully apply (effectively // turn into INSERT), because, although the table doesn't have any regular rows matching the // statement clustering column restriction, the static row matches the statement condition: // CREATE TABLE t(p int, c int, s int static, v int, PRIMARY KEY(p, c)); // INSERT INTO t(p, s) VALUES(1, 1); // UPDATE t SET v=1 WHERE p=1 AND c=1 IF s=1; if (op.ranges.empty()) { throw exceptions::invalid_request_exception("Empty clustering range"); } const clustering_key& ckey = op.ranges.front().start() ? op.ranges.front().start()->value() : empty_ckey; auto row = _rows.find_row(pkey, ckey); auto ckey_ptr = &ckey; if (row == nullptr && !ckey.is_empty() && !op.statement.has_if_exist_condition() && !op.statement.has_if_not_exist_condition()) { row = _rows.find_row(pkey, empty_ckey); ckey_ptr = &empty_ckey; } if (!row) { ckey_ptr = &empty_ckey; } return old_row{ckey_ptr, row}; } seastar::shared_ptr cas_request::build_cas_result_set(seastar::shared_ptr metadata, const column_set& columns, bool is_applied) const { const partition_key& pkey = _key.front().start()->value().key().value(); const clustering_key empty_ckey = clustering_key::make_empty(); auto result_set = std::make_unique(metadata); auto pkey_bytes = pkey.explode(); for (const cas_row_update& op: _updates) { // Construct the result set row std::vector rs_row; rs_row.reserve(metadata->value_count()); rs_row.emplace_back(boolean_type->decompose(is_applied)); // Get old row from prefetched data for the row update auto old_row = find_old_row(op); if (!old_row.row) { // In case there is no old row, leave all other columns null // so that we can infer whether the update attempts to insert a // non-existing row. rs_row.resize(metadata->value_count()); result_set->add_row(std::move(rs_row)); continue; } auto ckey_bytes = old_row.ckey->explode(); auto eval_inputs = expr::evaluation_inputs{ .partition_key = pkey_bytes, .clustering_key = ckey_bytes, .static_and_regular_columns = old_row.row->cells, .selection = _rows.selection.get(), }; // Fill in the cells from prefetch data (old row) into the result set row for (ordinal_column_id id = columns.find_first(); id != column_set::npos; id = columns.find_next(id)) { auto& cdef = _schema->column_at(id); auto val = expr::extract_column_value(&cdef, eval_inputs); if (!val) { rs_row.emplace_back(bytes_opt{}); continue; } const abstract_type& column_type = *cdef.type; if (column_type.is_listlike() && column_type.is_multi_cell()) { // List/sets are fetched as maps, but need to be stored as sets. const listlike_collection_type_impl& list_type = static_cast(column_type); auto map_type_holder = map_type_impl::get_instance(list_type.name_comparator(), list_type.value_comparator(), list_type.is_multi_cell()); const map_type_impl& map_type = static_cast(*map_type_holder); auto cell = map_type.deserialize(managed_bytes_view(*val)); rs_row.emplace_back(list_type.serialize_map(map_type, cell)); } else { rs_row.emplace_back(to_bytes(*val)); } } result_set->add_row(std::move(rs_row)); } cql3::result result(std::move(result_set)); return seastar::make_shared(std::move(result)); } } // end of namespace "cql3::statements"