ClickHouse/dbms/src/Parsers/ParserTablePropertiesQuery.cpp
2018-03-12 18:21:50 +03:00

90 lines
2.0 KiB
C++

#include <Parsers/ASTIdentifier.h>
#include <Parsers/TablePropertiesQueriesASTs.h>
#include <Parsers/CommonParsers.h>
#include <Parsers/ParserTablePropertiesQuery.h>
#include <Common/typeid_cast.h>
namespace DB
{
bool ParserTablePropertiesQuery::parseImpl(Pos & pos, ASTPtr & node, Expected & expected)
{
ParserKeyword s_exists("EXISTS");
ParserKeyword s_temporary("TEMPORARY");
ParserKeyword s_describe("DESCRIBE");
ParserKeyword s_desc("DESC");
ParserKeyword s_show("SHOW");
ParserKeyword s_create("CREATE");
ParserKeyword s_database("DATABASE");
ParserKeyword s_table("TABLE");
ParserToken s_dot(TokenType::Dot);
ParserIdentifier name_p;
ASTPtr database;
ASTPtr table;
std::shared_ptr<ASTQueryWithTableAndOutput> query;
bool parse_only_database_name = false;
if (s_exists.ignore(pos, expected))
{
query = std::make_shared<ASTExistsQuery>();
}
else if (s_show.ignore(pos, expected))
{
if (!s_create.ignore(pos, expected))
return false;
if (s_database.ignore(pos, expected))
{
parse_only_database_name = true;
query = std::make_shared<ASTShowCreateDatabaseQuery>();
}
else
query = std::make_shared<ASTShowCreateTableQuery>();
}
else
{
return false;
}
if (parse_only_database_name)
{
if (!name_p.parse(pos, database, expected))
return false;
}
else
{
if (s_temporary.ignore(pos, expected))
query->temporary = true;
s_table.ignore(pos, expected);
if (!name_p.parse(pos, table, expected))
return false;
if (s_dot.ignore(pos, expected))
{
database = table;
if (!name_p.parse(pos, table, expected))
return false;
}
}
if (database)
query->database = typeid_cast<ASTIdentifier &>(*database).name;
if (table)
query->table = typeid_cast<ASTIdentifier &>(*table).name;
node = query;
return true;
}
}