[bug](function) fix array_map cause coredump as NULL

be/src/vec/exprs/lambda_function/varray_map_function.cpp

@@ -185,6 +185,39 @@ class ArrayMapFunction : public LambdaFunction {
             data_types.push_back(col_type.get_nested_type());
         }
 
+        ColumnWithTypeAndName result_arr;
+        // if column_array is NULL, we know the array_data_column will not write any data,
+        // so the column is empty. eg : (x) -> concat('|',x + "1"). if still execute the lambda function, will cause the bolck rows are not equal
+        // the x column is empty, but "|" is const literal, size of column is 1, so the block rows is 1, but the x column is empty, will be coredump.
+        if (std::any_of(lambda_datas.begin(), lambda_datas.end(),
+                        [](const auto& v) { return v->empty(); })) {
+            DataTypePtr nested_type;
+            bool is_nullable = result_type->is_nullable();
+            if (is_nullable) {
+                nested_type =
+                        assert_cast<const DataTypeNullable*>(result_type.get())->get_nested_type();
+            } else {
+                nested_type = result_type;
+            }
+            auto empty_nested_column = assert_cast<const DataTypeArray*>(nested_type.get())
+                                               ->get_nested_type()
+                                               ->create_column();
+            auto result_array_column = ColumnArray::create(std::move(empty_nested_column),
+                                                           std::move(array_column_offset));
+
+            if (is_nullable) {
+                result_arr = {ColumnNullable::create(std::move(result_array_column),
+                                                     std::move(outside_null_map)),
+                              result_type, "Result"};
+            } else {
+                result_arr = {std::move(result_array_column), result_type, "Result"};
+            }
+
+            block->insert(result_arr);
+            *result_column_id = block->columns() - 1;
+            return Status::OK();
+        }
+
         MutableColumnPtr result_col = nullptr;
         DataTypePtr res_type;
         std::string res_name;
@@ -267,7 +300,6 @@ class ArrayMapFunction : public LambdaFunction {
         } while (args_info.current_row_idx < block->rows());
 
         //4. get the result column after execution, reassemble it into a new array column, and return.
-        ColumnWithTypeAndName result_arr;
         if (result_type->is_nullable()) {
             if (res_type->is_nullable()) {
                 result_arr = {

regression-test/data/query_p0/sql_functions/array_functions/test_array_map_function.out

@@ -123,3 +123,12 @@
 4	[[90, 100], [110, 120]]
 5	[[130]]
 
+-- !select_26 --
+\N
+
+-- !select_27 --
+\N	\N
+
+-- !select_28 --
+[]
+

regression-test/suites/query_p0/sql_functions/array_functions/test_array_map_function.groovy

@@ -103,6 +103,7 @@ suite("test_array_map_function") {
         }             
 
         sql "DROP TABLE IF EXISTS ${tableName}"
+        sql "DROP TABLE IF EXISTS array_map_test"
 
         sql """ CREATE TABLE IF NOT EXISTS array_map_test (
             id INT,
@@ -128,4 +129,46 @@ suite("test_array_map_function") {
         qt_select_25 """ 
             SELECT id, array_map(x -> array_map(y -> y * 10, x), nested_array) FROM array_map_test order by id;
         """ 
+
+        sql "DROP TABLE IF EXISTS db"
+
+        sql """ CREATE TABLE `db` (
+                `id` VARCHAR(255) NULL COMMENT '主键',
+                `QC_result_list` ARRAY<TEXT> NULL COMMENT '标签预刷'
+                ) ENGINE=OLAP
+                UNIQUE KEY(`id`)
+                DISTRIBUTED BY HASH(`id`) BUCKETS 10
+                PROPERTIES (
+                "replication_allocation" = "tag.location.default: 1",
+                "is_being_synced" = "false",
+                "storage_medium" = "hdd",
+                "storage_format" = "V2",
+                "enable_unique_key_merge_on_write" = "true",
+                "light_schema_change" = "true",
+                "disable_auto_compaction" = "false",
+                "enable_single_replica_compaction" = "false"
+                );
+        """
+
+        sql """insert into db values(1,null);
+        """
+
+        qt_select_26 """
+            select  array_map(
+                            (x, y, z) -> concat(
+                                '|',
+                                x + "1",
+                                '|',
+                                x + "2",
+                                '|',
+                                x + "3"
+                            ),
+                            QC_result_list,
+                            QC_result_list,
+                            QC_result_list
+                        ) FROM db; 
+        """
+
+        qt_select_27 """ select QC_result_list, array_map(                 x -> concat(                     '|',                     x + "1"                 ),                 QC_result_list             ) FROM db; """
+        qt_select_28 """ select array_map((x,y)->x,[],[]); """
 }