fix lagInFrame for nullable types

This commit is contained in:
Alexander Kuzmenkov 2021-07-19 19:31:57 +03:00
parent 19a83b75b7
commit 61a01782a6
4 changed files with 48 additions and 24 deletions

View File

@ -71,10 +71,19 @@ AggregateFunctionPtr AggregateFunctionFactory::get(
{
auto type_without_low_cardinality = convertLowCardinalityTypesToNested(argument_types);
/// If one of the types is Nullable, we apply aggregate function combinator "Null".
auto with_original_parameters = getImpl(name, type_without_low_cardinality, parameters, out_properties, false);
if (std::any_of(type_without_low_cardinality.begin(), type_without_low_cardinality.end(),
[](const auto & type) { return type->isNullable(); }))
// If one of the types is Nullable, we apply aggregate function combinator "Null".
// Pure window functions are not real aggregate functions. Applying
// combinators doesn't make sense for them, they must handle the
// nullability themselves. Another special case is functions from Nothing
// that are rewritten to AggregateFunctionNothing, in this case
// nested_function is nullptr.
if (!(with_original_parameters
&& with_original_parameters->isOnlyWindowFunction())
&& std::any_of(type_without_low_cardinality.begin(),
type_without_low_cardinality.end(),
[](const auto & type) { return type->isNullable(); }))
{
AggregateFunctionCombinatorPtr combinator = AggregateFunctionCombinatorFactory::instance().tryFindSuffix("Null");
if (!combinator)
@ -90,23 +99,12 @@ AggregateFunctionPtr AggregateFunctionFactory::get(
AggregateFunctionPtr nested_function = getImpl(
name, nested_types, nested_parameters, out_properties, has_null_arguments);
// Pure window functions are not real aggregate functions. Applying
// combinators doesn't make sense for them, they must handle the
// nullability themselves. Another special case is functions from Nothing
// that are rewritten to AggregateFunctionNothing, in this case
// nested_function is nullptr.
if (nested_function && nested_function->isOnlyWindowFunction())
{
return nested_function;
}
return combinator->transformAggregateFunction(nested_function, out_properties, type_without_low_cardinality, parameters);
}
auto res = getImpl(name, type_without_low_cardinality, parameters, out_properties, false);
if (!res)
if (!with_original_parameters)
throw Exception("Logical error: AggregateFunctionFactory returned nullptr", ErrorCodes::LOGICAL_ERROR);
return res;
return with_original_parameters;
}

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@ -1475,10 +1475,10 @@ struct WindowFunctionLagLeadInFrame final : public WindowFunction
return;
}
if (!getLeastSupertype({argument_types[0], argument_types[2]}))
if (!argument_types[0]->equals(*argument_types[2]))
{
throw Exception(ErrorCodes::BAD_ARGUMENTS,
"The default value type '{}' is not convertible to the argument type '{}'",
"The default value type '{}' is not the same as the argument type '{}'",
argument_types[2]->getName(),
argument_types[0]->getName());
}
@ -1491,8 +1491,7 @@ struct WindowFunctionLagLeadInFrame final : public WindowFunction
}
}
DataTypePtr getReturnType() const override
{ return argument_types[0]; }
DataTypePtr getReturnType() const override { return argument_types[0]; }
bool allocatesMemoryInArena() const override { return false; }

View File

@ -1056,10 +1056,25 @@ settings max_block_size = 3;
15 3 15 0 15 15 15
-- careful with auto-application of Null combinator
select lagInFrame(toNullable(1)) over ();
0
\N
select lagInFrameOrNull(1) over (); -- { serverError 36 }
select intDiv(1, NULL) x, toTypeName(x), max(x) over ();
\N Nullable(Nothing) \N
-- this should give the same error as `select max(Null::Nullable(Nothing))`
select intDiv(1, NULL) x, toTypeName(x), max(x) over (); -- { serverError 43 }
-- to make lagInFrame return null for out-of-frame rows, cast the argument to
-- Nullable; otherwise, it returns default values.
SELECT
number,
lagInFrame(toNullable(number), 1) OVER w,
lagInFrame(toNullable(number), 2) OVER w,
lagInFrame(number, 1) OVER w,
lagInFrame(number, 2) OVER w
FROM numbers(4)
WINDOW w AS (ORDER BY number ASC)
;
0 \N \N 0 0
1 0 \N 0 0
2 1 0 1 0
3 2 1 2 1
-- case-insensitive SQL-standard synonyms for any and anyLast
select
number,

View File

@ -379,7 +379,19 @@ settings max_block_size = 3;
-- careful with auto-application of Null combinator
select lagInFrame(toNullable(1)) over ();
select lagInFrameOrNull(1) over (); -- { serverError 36 }
select intDiv(1, NULL) x, toTypeName(x), max(x) over ();
-- this should give the same error as `select max(Null::Nullable(Nothing))`
select intDiv(1, NULL) x, toTypeName(x), max(x) over (); -- { serverError 43 }
-- to make lagInFrame return null for out-of-frame rows, cast the argument to
-- Nullable; otherwise, it returns default values.
SELECT
number,
lagInFrame(toNullable(number), 1) OVER w,
lagInFrame(toNullable(number), 2) OVER w,
lagInFrame(number, 1) OVER w,
lagInFrame(number, 2) OVER w
FROM numbers(4)
WINDOW w AS (ORDER BY number ASC)
;
-- case-insensitive SQL-standard synonyms for any and anyLast
select