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This commit is contained in:
divanik 2024-02-07 15:29:45 +00:00
parent 623b425745
commit 145e425ddd
3 changed files with 26 additions and 54 deletions
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25
docs/en/sql-reference/table-functions/generate_series.md Normal file
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@ -0,0 +1,25 @@
---
slug: /en/sql-reference/table-functions/generate_series
sidebar_position: ?
sidebar_label: generate_series
---
# generate_series
`generate_series(START, STOP)` - Returns a table with the single ‘generate_series’ column (UInt64) that contains integers from start to stop inclusively.
`generate_series(START, STOP, STEP)` - Returns a table with the single ‘generate_series’ column (UInt64) that contains integers from start to stop inclusively with spacing between values given by STEP.
The following queries return tables with the same content but different column names:
``` sql
SELECT * FROM numbers(10, 5);
SELECT * FROM generate_series(10, 14);
```
And the following queries return tables with the same content but different column names (but the second option is more efficient):
``` sql
SELECT * FROM numbers(10, 11) WHERE number % 3 == (10 % 3);
SELECT * FROM generate_series(10, 20, 3) ;
```

53
src/Processors/QueryPlan/ReadFromSystemNumbersStep.cpp
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@ -98,8 +98,6 @@ std::optional<RangeWithStep> stepped_range_from_range(const Range & r, UInt64 st
return std::nullopt;
begin += remainder;
// LOG_DEBUG(&Poco::Logger::get("stepped_range_from_range"), "Begin: {}", begin);
// LOG_DEBUG(&Poco::Logger::get("stepped_range_from_range"), "Begin: {}", begin);
while ((r.left_included <= r.left.get<UInt64>()) && (begin <= r.left.get<UInt64>() - r.left_included))
{
if (std::numeric_limits<UInt64>::max() - step < begin)
@ -107,7 +105,6 @@ std::optional<RangeWithStep> stepped_range_from_range(const Range & r, UInt64 st
begin += step;
}
// LOG_DEBUG(&Poco::Logger::get("stepped_range_from_range"), "Begin: {}", begin);
if ((begin >= r.right_included) && (begin - r.right_included >= r.right.get<UInt64>()))
return std::nullopt;
UInt64 right_edge_included = r.right.get<UInt64>() - (1 - r.right_included);
@ -217,9 +214,6 @@ protected:
ranges_state->pos = end;
LOG_DEBUG(&Poco::Logger::get("Range borders"), "Begin: {} {}", start.offset_in_ranges, static_cast<size_t>(start.offset_in_range));
LOG_DEBUG(&Poco::Logger::get("Range borders"), "End: {} {}", end.offset_in_ranges, static_cast<size_t>(end.offset_in_range));
return size;
}
@ -258,12 +252,6 @@ protected:
? end.offset_in_range - cursor.offset_in_range
: static_cast<UInt128>(last_value(range) - first_value(range)) / range.step + 1 - cursor.offset_in_range;
LOG_DEBUG(
&Poco::Logger::get("Generate"),
"Can Provide: {}, Block size: {}",
static_cast<UInt64>(can_provide),
static_cast<UInt64>(block_size));
/// set value to block
auto set_value = [&pos, this](UInt128 & start_value, UInt128 & end_value)
{
@ -280,8 +268,6 @@ protected:
auto start_value_64 = static_cast<UInt64>(start_value);
auto end_value_64 = static_cast<UInt64>(end_value);
auto size = (end_value_64 - start_value_64) / this->step;
LOG_DEBUG(
&Poco::Logger::get("Iota"), "Size: {}, Step: {}, Start: {}", static_cast<size_t>(size), this->step, start_value_64);
iota_with_step(pos, static_cast<size_t>(size), start_value_64, step);
pos += size;
}
@ -443,13 +429,6 @@ Pipe ReadFromSystemNumbersStep::makePipe()
{
auto & numbers_storage = storage->as<StorageSystemNumbers &>();
LOG_DEBUG(
&Poco::Logger::get("Parameters"),
"Parameters: Limit: {}, Offset: {} Step: {}",
numbers_storage.limit.value(),
numbers_storage.offset,
numbers_storage.step);
if (!numbers_storage.multithreaded)
num_streams = 1;
@ -468,7 +447,6 @@ Pipe ReadFromSystemNumbersStep::makePipe()
if (condition.extractPlainRanges(ranges))
{
LOG_DEBUG(&Poco::Logger::get("My logger"), "Use optimization");
/// Intersect ranges with table range
std::optional<Range> table_range;
std::optional<Range> overflowed_table_range;
@ -493,36 +471,11 @@ Pipe ReadFromSystemNumbersStep::makePipe()
{
table_range.emplace(FieldRef(numbers_storage.offset), true, FieldRef(std::numeric_limits<UInt64>::max()), true);
}
LOG_DEBUG(&Poco::Logger::get("My logger"), "Found table ranges");
RangesWithStep intersected_ranges;
for (auto & r : ranges)
{
auto intersected_range = table_range->intersectWith(r);
if (intersected_range.has_value())
{
LOG_DEBUG(
&Poco::Logger::get("Ranges"),
"Ranges: {} {} {} {}",
intersected_range->left.get<UInt64>(),
intersected_range->right.get<UInt64>(),
intersected_range->left_included,
intersected_range->right_included);
auto range_with_step = stepped_range_from_range(
intersected_range.value(), numbers_storage.step, numbers_storage.offset % numbers_storage.step);
if (range_with_step.has_value())
{
LOG_DEBUG(
&Poco::Logger::get("Ranges With Step"),
"Ranges: {} {} {} {} {}",
range_with_step->range.left.get<UInt64>(),
range_with_step->range.right.get<UInt64>(),
range_with_step->range.left_included,
range_with_step->range.right_included,
range_with_step->step);
intersected_ranges.push_back(*range_with_step);
}
}
}
@ -546,11 +499,6 @@ Pipe ReadFromSystemNumbersStep::makePipe()
}
}
// for (const auto& range : intersected_ranges)
// {
// LOG_DEBUG(&Poco::Logger::get("Ranges with step"), "Left: {}; Right {}, LI: {}, RI: {}, Step: {}", range.range.left.get<UInt64>(), range.range.right.get<UInt64>(), range.range.left_included, range.range.right_included, range.step);
// // std::cout <<
// }
/// ranges is blank, return a source who has no data
if (intersected_ranges.empty())
@ -565,7 +513,6 @@ Pipe ReadFromSystemNumbersStep::makePipe()
if (!intersected_ranges.rbegin()->range.right.isPositiveInfinity() || should_pushdown_limit)
{
UInt128 total_size = sizeOfRanges(intersected_ranges);
LOG_DEBUG(&Poco::Logger::get("Total_Size"), "Total Size: {}", static_cast<UInt64>(total_size));
UInt128 query_limit = limit_length + limit_offset;
/// limit total_size by query_limit

2
src/Storages/System/StorageSystemNumbers.h
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@ -43,7 +43,7 @@ private:
bool multithreaded;
std::optional<UInt64> limit;
UInt64 offset;`
UInt64 offset;
std::string column_name;
UInt64 step;
};