ClickHouse/src/Interpreters/SelectQueryOptions.h

179 lines
5.3 KiB
C++

#pragma once
#include <Core/QueryProcessingStage.h>
#include <optional>
namespace DB
{
/**
* to_stage
* - the stage to which the query is to be executed. By default - till to the end.
* You can perform till the intermediate aggregation state, which are combined from different servers for distributed query processing.
*
* subquery_depth
* - to control the limit on the depth of nesting of subqueries. For subqueries, a value that is incremented by one is passed;
* for INSERT SELECT, a value 1 is passed instead of 0.
*
* only_analyze
* - the object was created only for query analysis.
*
* is_subquery
* - there could be some specific for subqueries. Ex. there's no need to pass duplicated columns in results, cause of indirect results.
*
* is_internal
* - the object was created only for internal queries.
*/
struct SelectQueryOptions
{
QueryProcessingStage::Enum to_stage;
size_t subquery_depth;
bool only_analyze = false;
bool modify_inplace = false;
bool remove_duplicates = false;
bool ignore_quota = false;
bool ignore_limits = false;
/// This flag is needed to analyze query ignoring table projections.
/// It is needed because we build another one InterpreterSelectQuery while analyzing projections.
/// It helps to avoid infinite recursion.
bool ignore_projections = false;
/// This flag is also used for projection analysis.
/// It is needed because lazy normal projections require special planning in FetchColumns stage, such as adding WHERE transform.
/// It is also used to avoid adding aggregating step when aggregate projection is chosen.
bool is_projection_query = false;
/// This flag is needed for projection description.
/// Otherwise, keys for GROUP BY may be removed as constants.
bool ignore_ast_optimizations = false;
bool ignore_alias = false;
bool is_internal = false;
bool is_subquery = false; // non-subquery can also have subquery_depth > 0, e.g. insert select
bool with_all_cols = false; /// asterisk include materialized and aliased columns
bool settings_limit_offset_done = false;
bool is_explain = false; /// The value is true if it's explain statement.
bool is_create_parameterized_view = false;
/// Bypass setting constraints for some internal queries such as projection ASTs.
bool ignore_setting_constraints = false;
/// These two fields are used to evaluate shardNum() and shardCount() function when
/// prefer_localhost_replica == 1 and local instance is selected. They are needed because local
/// instance might have multiple shards and scalars can only hold one value.
std::optional<UInt32> shard_num;
std::optional<UInt32> shard_count;
SelectQueryOptions(
QueryProcessingStage::Enum stage = QueryProcessingStage::Complete,
size_t depth = 0,
bool is_subquery_ = false,
bool settings_limit_offset_done_ = false)
: to_stage(stage), subquery_depth(depth), is_subquery(is_subquery_),
settings_limit_offset_done(settings_limit_offset_done_)
{}
SelectQueryOptions copy() const { return *this; }
SelectQueryOptions subquery() const
{
SelectQueryOptions out = *this;
out.to_stage = QueryProcessingStage::Complete;
++out.subquery_depth;
out.is_subquery = true;
return out;
}
SelectQueryOptions createParameterizedView() const
{
SelectQueryOptions out = *this;
out.is_create_parameterized_view = true;
return out;
}
SelectQueryOptions & analyze(bool dry_run = true)
{
only_analyze = dry_run;
return *this;
}
SelectQueryOptions & modify(bool value = true)
{
modify_inplace = value;
return *this;
}
SelectQueryOptions & noModify() { return modify(false); }
SelectQueryOptions & removeDuplicates(bool value = true)
{
remove_duplicates = value;
return *this;
}
SelectQueryOptions & noSubquery()
{
subquery_depth = 0;
return *this;
}
SelectQueryOptions & ignoreLimits(bool value = true)
{
ignore_limits = value;
return *this;
}
SelectQueryOptions & ignoreProjections(bool value = true)
{
ignore_projections = value;
return *this;
}
SelectQueryOptions & projectionQuery(bool value = true)
{
is_projection_query = value;
return *this;
}
SelectQueryOptions & ignoreAlias(bool value = true)
{
ignore_alias = value;
return *this;
}
SelectQueryOptions & ignoreASTOptimizations(bool value = true)
{
ignore_ast_optimizations = value;
return *this;
}
SelectQueryOptions & ignoreSettingConstraints(bool value = true)
{
ignore_setting_constraints = value;
return *this;
}
SelectQueryOptions & setInternal(bool value = false)
{
is_internal = value;
return *this;
}
SelectQueryOptions & setWithAllColumns(bool value = true)
{
with_all_cols = value;
return *this;
}
SelectQueryOptions & setShardInfo(UInt32 shard_num_, UInt32 shard_count_)
{
shard_num = shard_num_;
shard_count = shard_count_;
return *this;
}
SelectQueryOptions & setExplain(bool value = true)
{
is_explain = value;
return *this;
}
};
}