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dbms: Sending only required external tables to remote servers [METR-10071]

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This commit is contained in:
Sergey Fedorov 2014-04-01 18:06:58 +04:00
parent e426667931
commit fff1593bd9
3 changed files with 43 additions and 6 deletions
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5
dbms/include/DB/Interpreters/ExpressionAnalyzer.h
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@ -100,7 +100,7 @@ public:
Block getSelectSampleBlock();
/// Все новые временные таблицы, полученные при выполнении подзапросов GLOBAL IN.
std::vector<StoragePtr> external_tables;
Tables external_tables;
private:
typedef std::set<String> NamesSet;
@ -263,7 +263,8 @@ private:
/// Обходит запрос и сохраняет найденные глобальные функции (например GLOBAL IN)
void findGlobalFunctions(ASTPtr & ast, std::vector<ASTPtr> & global_nodes);
void findExternalTables(ASTPtr & ast);
/// Превратить перечисление значений или подзапрос в ASTSet. node - функция in или notIn.
void makeSet(ASTFunction * node, const Block & sample_block);
/// Выполнить подзапрос в секции GLOBAL IN и запомнить результат во временную таблицу типа memory

39
dbms/src/Interpreters/ExpressionAnalyzer.cpp
View File

@ -516,6 +516,34 @@ void ExpressionAnalyzer::findGlobalFunctions(ASTPtr & ast, std::vector<ASTPtr> &
}
void ExpressionAnalyzer::findExternalTables(ASTPtr & ast)
{
/// Рекурсивные вызовы. Намеренно опускаемся в подзапросы.
for (ASTs::iterator it = ast->children.begin(); it != ast->children.end(); ++it)
findExternalTables(*it);
/// Если идентификатор типа таблица
StoragePtr external_storage;
if (ASTIdentifier * node = dynamic_cast<ASTIdentifier *>(&*ast))
if (node->kind == ASTIdentifier::Kind::Table)
if (external_storage = context.tryGetExternalTable(node->name))
external_tables[node->name] = external_storage;
if (ASTFunction * node = dynamic_cast<ASTFunction *>(&*ast))
{
if (node->name == "globalIn" || node->name == "globalNotIn" || node->name == "In" || node->name == "NotIn")
{
IAST & args = *node->arguments;
ASTPtr & arg = args.children[1];
/// Если имя таблицы для селекта
if (ASTIdentifier * id = dynamic_cast<ASTIdentifier *>(&*arg))
if (external_storage = context.tryGetExternalTable(id->name))
external_tables[id->name] = external_storage;
}
}
}
void ExpressionAnalyzer::addExternalStorage(ASTFunction * node, size_t & name_id)
{
IAST & args = *node->arguments;
@ -542,8 +570,13 @@ void ExpressionAnalyzer::addExternalStorage(ASTFunction * node, size_t & name_id
{
ParserSelectQuery parser;
if (context.tryGetExternalTable(table->name))
StoragePtr existing_storage;
if (existing_storage = context.tryGetExternalTable(table->name))
{
external_tables[table->name] = existing_storage;
return;
}
String query = "SELECT * FROM " + table->name;
const char * begin = query.data();
@ -573,7 +606,7 @@ void ExpressionAnalyzer::addExternalStorage(ASTFunction * node, size_t & name_id
ast_ident->kind = ASTIdentifier::Table;
ast_ident->name = external_storage->getTableName();
arg = ast_ident;
external_tables.push_back(external_storage);
external_tables[external_table_name] = external_storage;
}
else
throw Exception("GLOBAL [NOT] IN supports only SELECT data.", ErrorCodes::BAD_ARGUMENTS);
@ -1177,6 +1210,8 @@ void ExpressionAnalyzer::processGlobalOperations()
++id;
addExternalStorage(dynamic_cast<ASTFunction *>(&*global_nodes[i]), id);
}
findExternalTables(ast);
}
bool ExpressionAnalyzer::appendArrayJoin(ExpressionActionsChain & chain, bool only_types)

5
dbms/src/Interpreters/InterpreterSelectQuery.cpp
View File

@ -83,7 +83,8 @@ void InterpreterSelectQuery::init(BlockInputStreamPtr input_, const NamesAndType
/// Сохраняем в query context новые временные таблицы
for (auto & it : query_analyzer->external_tables)
context.addExternalTable(it->getTableName(), it);
if (!(context.tryGetExternalTable(it.first)))
context.addExternalTable(it.first, it.second);
if (input_)
streams.push_back(input_);
@ -504,7 +505,7 @@ QueryProcessingStage::Enum InterpreterSelectQuery::executeFetchColumns(BlockInpu
if (!interpreter_subquery)
{
if (storage->isRemote())
storage->storeExternalTables(context.getExternalTables());
storage->storeExternalTables(query_analyzer->external_tables);
streams = storage->read(required_columns, query_ptr, settings_for_storage, from_stage, settings.max_block_size, settings.max_threads);
for (auto stream : streams)
{