mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-12-12 17:32:32 +00:00
113 lines
3.8 KiB
C++
113 lines
3.8 KiB
C++
/* Copyright (c) 2018 BlackBerry Limited
|
|
|
|
Licensed under the Apache License, Version 2.0 (the "License");
|
|
you may not use this file except in compliance with the License.
|
|
You may obtain a copy of the License at
|
|
http://www.apache.org/licenses/LICENSE-2.0
|
|
Unless required by applicable law or agreed to in writing, software
|
|
distributed under the License is distributed on an "AS IS" BASIS,
|
|
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
See the License for the specific language governing permissions and
|
|
limitations under the License. */
|
|
#include <Core/Settings.h>
|
|
#include <Common/typeid_cast.h>
|
|
#include <Parsers/ASTWatchQuery.h>
|
|
#include <Interpreters/InterpreterWatchQuery.h>
|
|
#include <DataStreams/IBlockInputStream.h>
|
|
#include <DataStreams/OneBlockInputStream.h>
|
|
|
|
|
|
namespace DB
|
|
{
|
|
|
|
namespace ErrorCodes
|
|
{
|
|
extern const int UNKNOWN_STORAGE;
|
|
extern const int UNKNOWN_TABLE;
|
|
extern const int TOO_MANY_COLUMNS;
|
|
extern const int SUPPORT_IS_DISABLED;
|
|
}
|
|
|
|
BlockInputStreamPtr InterpreterWatchQuery::executeImpl()
|
|
{
|
|
return std::make_shared<OneBlockInputStream>(Block());
|
|
}
|
|
|
|
BlockIO InterpreterWatchQuery::execute()
|
|
{
|
|
if (!context.getSettingsRef().allow_experimental_live_view)
|
|
throw Exception("Experimental LIVE VIEW feature is not enabled (the setting 'allow_experimental_live_view')", ErrorCodes::SUPPORT_IS_DISABLED);
|
|
|
|
BlockIO res;
|
|
const ASTWatchQuery & query = typeid_cast<const ASTWatchQuery &>(*query_ptr);
|
|
String database;
|
|
String table;
|
|
/// Get database
|
|
if (!query.database.empty())
|
|
database = query.database;
|
|
else
|
|
database = context.getCurrentDatabase();
|
|
|
|
/// Get table
|
|
table = query.table;
|
|
|
|
/// Get storage
|
|
storage = context.tryGetTable(database, table);
|
|
|
|
if (!storage)
|
|
throw Exception("Table " + backQuoteIfNeed(database) + "." +
|
|
backQuoteIfNeed(table) + " doesn't exist.",
|
|
ErrorCodes::UNKNOWN_TABLE);
|
|
|
|
/// List of columns to read to execute the query.
|
|
Names required_columns = storage->getColumns().getNamesOfPhysical();
|
|
|
|
/// Get context settings for this query
|
|
const Settings & settings = context.getSettingsRef();
|
|
|
|
/// Limitation on the number of columns to read.
|
|
if (settings.max_columns_to_read && required_columns.size() > settings.max_columns_to_read)
|
|
throw Exception("Limit for number of columns to read exceeded. "
|
|
"Requested: " + std::to_string(required_columns.size())
|
|
+ ", maximum: " + settings.max_columns_to_read.toString(),
|
|
ErrorCodes::TOO_MANY_COLUMNS);
|
|
|
|
size_t max_block_size = settings.max_block_size;
|
|
size_t max_streams = 1;
|
|
|
|
/// Define query info
|
|
SelectQueryInfo query_info;
|
|
query_info.query = query_ptr;
|
|
|
|
/// From stage
|
|
QueryProcessingStage::Enum from_stage = QueryProcessingStage::FetchColumns;
|
|
QueryProcessingStage::Enum to_stage = QueryProcessingStage::Complete;
|
|
|
|
/// Watch storage
|
|
streams = storage->watch(required_columns, query_info, context, from_stage, max_block_size, max_streams);
|
|
|
|
/// Constraints on the result, the quota on the result, and also callback for progress.
|
|
if (IBlockInputStream * stream = dynamic_cast<IBlockInputStream *>(streams[0].get()))
|
|
{
|
|
/// Constraints apply only to the final result.
|
|
if (to_stage == QueryProcessingStage::Complete)
|
|
{
|
|
IBlockInputStream::LocalLimits limits;
|
|
limits.mode = IBlockInputStream::LIMITS_CURRENT;
|
|
limits.size_limits.max_rows = settings.max_result_rows;
|
|
limits.size_limits.max_bytes = settings.max_result_bytes;
|
|
limits.size_limits.overflow_mode = settings.result_overflow_mode;
|
|
|
|
stream->setLimits(limits);
|
|
stream->setQuota(context.getQuota());
|
|
}
|
|
}
|
|
|
|
res.in = streams[0];
|
|
|
|
return res;
|
|
}
|
|
|
|
|
|
}
|