[Feature](docs) Impl the function map_concat like spark

docs/sql-manual/sql-functions/scalar-functions/map-functions/map-concat.md

@@ -0,0 +1,72 @@
+---
+{
+    "title": "MAP_CONCAT",
+    "language": "en"
+}
+---
+
+## Description
+
+Concatenates multiple maps into a single map.
+
+## Syntax
+
+```sql
+MAP_CONCAT(<map1> [, <map2> [, <map3> ... ]])
+```
+
+## Parameters
+- `<map1>`, `<map2>`, `<map3>`, ...: [`MAP`](../../../basic-element/sql-data-types/semi-structured/MAP.md) type, the input maps to concatenate.
+
+## Return Value
+Returns a concatenated `MAP` containing all key-value pairs from the input maps.
+
+## Usage Notes
+1. The function accepts zero or more map arguments.
+2. If any argument is NULL, the result is NULL.
+
+## Examples
+1. Basic usage
+    ```sql
+    select map_concat() as empty_map;
+    ```
+    ```text
+    +-----------+
+    | empty_map |
+    +-----------+
+    | {}        |
+    +-----------+
+    ```
+
+    ```sql
+    select map_concat(map('single', 'argument')) as single_argument;
+    ```
+    ```text
+    +-----------------+
+    | single_argument |
+    +-----------------+
+    | {"single":"argument"} |
+    +-----------------+
+    ```
+
+    ```sql
+    select map_concat({'a': 'apple'}, {'b': 'banana'}, {'c': 'cherry'}) as literal_maps_merged;
+    ```
+    ```text
+    +-------------------------------+
+    | literal_maps_merged           |
+    +-------------------------------+
+    | {"a":"apple", "b":"banana", "c":"cherry"} |
+    +-------------------------------+
+    ```
+
+2. NULL parameters
+    ```sql
+    select map_concat({'a': 'apple'}, NULL) as with_null;
+    ```
+    ```text
+    +------------+
+    | with_null  |
+    +------------+
+    | NULL       |
+    +------------+

i18n/zh-CN/docusaurus-plugin-content-docs/version-4.x/sql-manual/sql-functions/scalar-functions/map-functions/map-concat.md

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+---
+{
+    "title": "MAP_CONCAT",
+    "language": "zh-CN"
+}
+---
+
+## 描述
+
+将多个 map 合并为一个 map。
+
+## 语法
+
+```sql
+MAP_CONCAT(<map1> [, <map2> [, <map3> ... ]])
+```
+
+## 参数
+
+| 参数 | 说明 |
+| -- | -- |
+| `<map1>`, `<map2>`, `<map3>`, ... | [`MAP`](../../../basic-element/sql-data-types/semi-structured/MAP.md) 类型，需要合并的输入 map |
+
+## 返回值
+
+返回一个合并后的 `MAP`，包含所有输入 map 中的键值对。
+
+## 使用说明
+
+1. 该函数接受零个或多个 map 参数。
+2. 如果任何参数为 NULL，则结果为 NULL。
+
+## 示例
+
+1. 基本用法
+    ```sql
+    select map_concat() as empty_map;
+    ```
+    ```text
+    +-----------+
+    | empty_map |
+    +-----------+
+    | {}        |
+    +-----------+
+    ```
+
+    ```sql
+    select map_concat(map('single', 'argument')) as single_argument;
+    ```
+    ```text
+    +-----------------+
+    | single_argument |
+    +-----------------+
+    | {"single":"argument"} |
+    +-----------------+
+    ```
+
+    ```sql
+    select map_concat({'a': 'apple'}, {'b': 'banana'}, {'c': 'cherry'}) as literal_maps_merged;
+    ```
+    ```text
+    +-------------------------------+
+    | literal_maps_merged           |
+    +-------------------------------+
+    | {"a":"apple", "b":"banana", "c":"cherry"} |
+    +-------------------------------+
+    ```
+
+2. NULL 参数
+    ```sql
+    select map_concat({'a': 'apple'}, NULL) as with_null;
+    ```
+    ```text
+    +------------+
+    | with_null  |
+    +------------+
+    | NULL       |
+    +------------+
+    ```

versioned_sidebars/version-4.x-sidebars.json

@@ -1631,7 +1631,8 @@
                                         "sql-manual/sql-functions/scalar-functions/map-functions/map-keys",
                                         "sql-manual/sql-functions/scalar-functions/map-functions/map-size",
                                         "sql-manual/sql-functions/scalar-functions/map-functions/map-values",
-                                        "sql-manual/sql-functions/scalar-functions/map-functions/str-to-map"
+                                        "sql-manual/sql-functions/scalar-functions/map-functions/str-to-map",
+                                        "sql-manual/sql-functions/scalar-functions/map-functions/map-concat"
                                     ]
                                 },
                                 {