ClickHouse/dbms/src/Interpreters/InterpreterExistsQuery.cpp
2018-03-02 19:06:11 +08:00

45 lines
1.1 KiB
C++

#include <Storages/IStorage.h>
#include <Parsers/TablePropertiesQueriesASTs.h>
#include <DataStreams/OneBlockInputStream.h>
#include <DataStreams/BlockIO.h>
#include <DataStreams/copyData.h>
#include <DataTypes/DataTypesNumber.h>
#include <Columns/ColumnsNumber.h>
#include <Interpreters/Context.h>
#include <Interpreters/InterpreterExistsQuery.h>
#include <Common/typeid_cast.h>
namespace DB
{
BlockIO InterpreterExistsQuery::execute()
{
BlockIO res;
res.in = executeImpl();
return res;
}
Block InterpreterExistsQuery::getSampleBlock()
{
return Block{{
ColumnUInt8::create(),
std::make_shared<DataTypeUInt8>(),
"result" }};
}
BlockInputStreamPtr InterpreterExistsQuery::executeImpl()
{
const ASTExistsQuery & ast = typeid_cast<const ASTExistsQuery &>(*query_ptr);
bool res = ast.temporary ? context.isExternalTableExist(ast.table) : context.isTableExist(ast.database, ast.table);
return std::make_shared<OneBlockInputStream>(Block{{
ColumnUInt8::create(1, res),
std::make_shared<DataTypeUInt8>(),
"result" }});
}
}