Add tupleConcat function

docs/en/sql-reference/data-types/tuple.md

@@ -4,7 +4,7 @@ sidebar_position: 54
 sidebar_label: Tuple(T1, T2, ...)
 ---
 
-# Tuple(t1, T2, …)
+# Tuple(T1, T2, …)
 
 A tuple of elements, each having an individual [type](../../sql-reference/data-types/index.md#data_types). Tuple must contain at least one element.
 

docs/en/sql-reference/functions/array-functions.md

@@ -183,9 +183,8 @@ arrayConcat(arrays)
 **Arguments**
 
 - `arrays` – Arbitrary number of arguments of [Array](../../sql-reference/data-types/array.md) type.
-    **Example**
 
-<!-- -->
+**Example**
 
 ``` sql
 SELECT arrayConcat([1, 2], [3, 4], [5, 6]) AS res

docs/en/sql-reference/functions/tuple-functions.md

@@ -559,6 +559,29 @@ Result:
 └────────────────────────────┘
 ```
 
+## tupleConcat
+
+Combines tuples passed as arguments.
+
+``` sql
+tupleConcat(tuples)
+```
+
+**Arguments**
+
+- `tuples` – Arbitrary number of arguments of [Tuple](../../sql-reference/data-types/tuple.md) type.
+
+**Example**
+
+``` sql
+SELECT tupleConcat((1, 2), (3, 4), (true, false)) AS res
+```
+
+``` text
+┌─res──────────────────┐
+│ (1,2,3,4,true,false) │
+└──────────────────────┘
+```
 
 ## Distance functions
 

src/Functions/concat.cpp

@@ -208,6 +208,10 @@ public:
         {
             return FunctionFactory::instance().getImpl("mapConcat", context)->build(arguments);
         }
+        else if (isTuple(arguments.at(0).type))
+        {
+            return FunctionFactory::instance().getImpl("tupleConcat", context)->build(arguments);
+        }
         else
             return std::make_unique<FunctionToFunctionBaseAdaptor>(
                 FunctionConcat::create(context), collections::map<DataTypes>(arguments, [](const auto & elem) { return elem.type; }), return_type);

src/Functions/tupleConcat.cpp

@@ -0,0 +1,102 @@
+#include <Columns/ColumnTuple.h>
+#include <DataTypes/DataTypeTuple.h>
+#include <Functions/FunctionFactory.h>
+#include <Functions/FunctionHelpers.h>
+#include <Functions/IFunction.h>
+
+namespace DB
+{
+namespace ErrorCodes
+{
+    extern const int ILLEGAL_TYPE_OF_ARGUMENT;
+    extern const int NUMBER_OF_ARGUMENTS_DOESNT_MATCH;
+    extern const int ILLEGAL_COLUMN;
+}
+
+/// tupleConcat(tup1, ...) - concatenate tuples.
+class FunctionTupleConcat : public IFunction
+{
+public:
+    static constexpr auto name = "tupleConcat";
+    static FunctionPtr create(ContextPtr) { return std::make_shared<FunctionTupleConcat>(); }
+
+    String getName() const override { return name; }
+
+    bool isVariadic() const override { return true; }
+
+    size_t getNumberOfArguments() const override { return 0; }
+
+    bool isSuitableForShortCircuitArgumentsExecution(const DataTypesWithConstInfo & /*arguments*/) const override { return true; }
+
+    bool useDefaultImplementationForConstants() const override { return true; }
+
+    DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
+    {
+        if (arguments.empty())
+            throw Exception(
+                ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH,
+                "Function {} requires at least one argument.",
+                getName());
+
+        DataTypes tuple_arg_types;
+
+        for (const auto arg_idx : collections::range(0, arguments.size()))
+        {
+            const auto * arg = arguments[arg_idx].get();
+            if (!isTuple(arg))
+                throw Exception(
+                    ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT,
+                    "Illegal type {} of argument {} of function {}",
+                    arg->getName(),
+                    arg_idx + 1,
+                    getName());
+
+            const auto * type = checkAndGetDataType<DataTypeTuple>(arg);
+            for (const auto & elem : type->getElements())
+                tuple_arg_types.push_back(elem);
+        }
+
+        return std::make_shared<DataTypeTuple>(tuple_arg_types);
+    }
+
+    ColumnPtr executeImpl(const ColumnsWithTypeAndName & arguments, const DataTypePtr &, size_t) const override
+    {
+        const size_t num_arguments = arguments.size();
+        Columns columns;
+
+        for (size_t i = 0; i < num_arguments; i++)
+        {
+            const DataTypeTuple * arg_type = checkAndGetDataType<DataTypeTuple>(arguments[i].type.get());
+
+            if (!arg_type)
+                throw Exception(
+                    ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT,
+                    "Illegal type {} of argument {} of function {}",
+                    arguments[i].type->getName(),
+                    i + 1,
+                    getName());
+
+            ColumnPtr arg_col = arguments[i].column->convertToFullColumnIfConst();
+            const ColumnTuple * tuple_col = checkAndGetColumn<ColumnTuple>(arg_col.get());
+
+            if (!tuple_col)
+                throw Exception(
+                    ErrorCodes::ILLEGAL_COLUMN,
+                    "Illegal column {} of argument of function {}",
+                    arguments[i].column->getName(),
+                    getName());
+
+            for (const auto & inner_col : tuple_col->getColumns())
+                columns.push_back(inner_col);
+        }
+
+        return ColumnTuple::create(columns);
+    }
+};
+
+REGISTER_FUNCTION(TupleConcat)
+{
+    factory.registerFunction<FunctionTupleConcat>();
+}
+
+}

tests/queries/0_stateless/02833_tuple_concat.reference

@@ -0,0 +1,6 @@
+(1,'y',2,'n')
+(1,'y',2,'n',3,'n')
+(1,2,3,'a','b','c','2020-10-08','2020-11-08')	1	2	3	a	b	c	2020-10-08	2020-11-08
+(1,2,1,2)	1	2	1	2
+(1,2,3,4)	1	2	3	4
+(3,4,1,2)	3	4	1	2

tests/queries/0_stateless/02833_tuple_concat.sql

@@ -0,0 +1,23 @@
+SELECT tupleConcat(); -- { serverError NUMBER_OF_ARGUMENTS_DOESNT_MATCH }
+SELECT tupleConcat((1, 'y'), 1); -- { serverError ILLEGAL_TYPE_OF_ARGUMENT }
+
+SELECT tupleConcat((1, 'y'), (2, 'n'));
+SELECT tupleConcat((1, 'y'), (2, 'n'), (3, 'n'));
+
+WITH (1,2,3) || ('a','b','c') || ('2020-10-08'::Date, '2020-11-08'::Date) AS t
+SELECT t, t.1, t.2, t.3, t.4, t.5, t.6, t.7, t.8;
+
+DROP TABLE IF EXISTS t_02833;
+CREATE TABLE t_02833 (tup Tuple(a UInt64, b UInt64)) ENGINE=Log;
+INSERT INTO t_02833 VALUES ((1, 2));
+
+WITH (tup || tup) AS res
+SELECT res, res.1, res.2, res.3, res.4 FROM t_02833;
+
+WITH (tup || (3, 4)) AS res
+SELECT res, res.1, res.2, res.3, res.4 FROM t_02833;
+
+WITH ((3, 4) || tup) AS res
+SELECT res, res.1, res.2, res.3, res.4 FROM t_02833;
+
+DROP TABLE t_02833;