[Feature](func) Support table function json_each, json_each_text

docs/sql-manual/sql-functions/table-functions/json-each-outer.md

@@ -0,0 +1,91 @@
+---
+{
+    "title": "JSON_EACH_OUTER",
+    "language": "en",
+    "description": "Expands the top-level JSON object into a set of key/value pairs, where the value column retains JSON type. Unlike json_each, returns one row of NULLs instead of 0 rows when input is NULL or an empty object. Must be used with LATERAL VIEW."
+}
+---
+
+## Description
+
+The `json_each_outer` table function expands the top-level JSON object into a set of key/value pairs. Each row contains one key (`key`) and its corresponding value (`value`). The `value` column retains the JSON type, so string values are returned with JSON quotes preserved.
+
+Unlike [`json_each`](json-each.md), when the input is NULL or an empty object, `json_each_outer` returns one row of `NULL, NULL` instead of 0 rows.
+
+Must be used with [`LATERAL VIEW`](../../../query-data/lateral-view.md).
+
+## Syntax
+
+```sql
+JSON_EACH_OUTER(<json_str>)
+```
+
+## Parameters
+
+| Parameter    | Description                                                   |
+| ------------ | ------------------------------------------------------------- |
+| `<json_str>` | The JSON string to expand. The content must be a JSON object. |
+
+## Return Value
+
+Returns multi-column, multi-row data. Each row corresponds to one key-value pair in the JSON object:
+
+| Column  | Type   | Description                                                                             |
+| ------- | ------ | --------------------------------------------------------------------------------------- |
+| `key`   | String | The key name from the JSON object                                                       |
+| `value` | JSON   | The corresponding value, kept as JSON type (string values include quotes, e.g. `"foo"`) |
+
+Special cases:
+- If `<json_str>` is NULL, returns 1 row of `NULL, NULL`
+- If `<json_str>` is an empty object (`{}`), returns 1 row of `NULL, NULL`
+
+## Examples
+
+Basic usage: expand a JSON object with string values
+
+```sql
+SELECT k, v
+FROM (SELECT 1) dummy
+LATERAL VIEW json_each_outer('{"a":"foo","b":"bar"}') t AS k, v;
+```
+
+```text
++---+-------+
+| k | v     |
++---+-------+
+| a | "foo" |
+| b | "bar" |
++---+-------+
+```
+
+NULL parameter: returns 1 row of NULL
+
+```sql
+SELECT k, v
+FROM (SELECT 1) dummy
+LATERAL VIEW json_each_outer(NULL) t AS k, v;
+```
+
+```text
++------+------+
+| k    | v    |
++------+------+
+| NULL | NULL |
++------+------+
+```
+
+Empty object: returns 1 row of NULL
+
+```sql
+SELECT k, v
+FROM (SELECT 1) dummy
+LATERAL VIEW json_each_outer('{}') t AS k, v;
+```
+
+```text
++------+------+
+| k    | v    |
++------+------+
+| NULL | NULL |
++------+------+
+```

docs/sql-manual/sql-functions/table-functions/json-each-text-outer.md

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+---
+{
+    "title": "JSON_EACH_TEXT_OUTER",
+    "language": "en",
+    "description": "Expands the top-level JSON object into a set of key/value pairs, where the value column is returned as plain text. Unlike json_each_text, returns one row of NULLs instead of 0 rows when input is NULL or an empty object. Must be used with LATERAL VIEW."
+}
+---
+
+## Description
+
+The `json_each_text_outer` table function expands the top-level JSON object into a set of key/value pairs. Each row contains one key (`key`) and its corresponding value (`value`). Unlike [`json_each_outer`](json-each-outer.md), the `value` column is of type TEXT, so string values are returned **without** JSON quotes.
+
+Unlike [`json_each_text`](json-each-text.md), when the input is NULL or an empty object, `json_each_text_outer` returns one row of `NULL, NULL` instead of 0 rows.
+
+Must be used with [`LATERAL VIEW`](../../../query-data/lateral-view.md).
+
+## Syntax
+
+```sql
+JSON_EACH_TEXT_OUTER(<json_str>)
+```
+
+## Parameters
+
+| Parameter    | Description                                                   |
+| ------------ | ------------------------------------------------------------- |
+| `<json_str>` | The JSON string to expand. The content must be a JSON object. |
+
+## Return Value
+
+Returns multi-column, multi-row data. Each row corresponds to one key-value pair in the JSON object:
+
+| Column  | Type | Description                                                                      |
+| ------- | ---- | -------------------------------------------------------------------------------- |
+| `key`   | TEXT | The key name from the JSON object                                                |
+| `value` | TEXT | The corresponding value as plain text (string values have no quotes, e.g. `foo`) |
+
+Special cases:
+- If `<json_str>` is NULL, returns 1 row of `NULL, NULL`
+- If `<json_str>` is an empty object (`{}`), returns 1 row of `NULL, NULL`
+- A JSON `null` value is returned as SQL `NULL`
+
+## Examples
+
+Basic usage: expand a JSON object with string values
+
+```sql
+SELECT k, v
+FROM (SELECT 1) dummy
+LATERAL VIEW json_each_text_outer('{"a":"foo","b":"bar"}') t AS k, v;
+```
+
+```text
++---+-----+
+| k | v   |
++---+-----+
+| a | foo |
+| b | bar |
++---+-----+
+```
+
+> The `value` column is of TEXT type, so string values have **no** JSON quotes (unlike `json_each_outer`).
+
+NULL parameter: returns 1 row of NULL
+
+```sql
+SELECT k, v
+FROM (SELECT 1) dummy
+LATERAL VIEW json_each_text_outer(NULL) t AS k, v;
+```
+
+```text
++------+------+
+| k    | v    |
++------+------+
+| NULL | NULL |
++------+------+
+```
+
+Empty object: returns 1 row of NULL
+
+```sql
+SELECT k, v
+FROM (SELECT 1) dummy
+LATERAL VIEW json_each_text_outer('{}') t AS k, v;
+```
+
+```text
++------+------+
+| k    | v    |
++------+------+
+| NULL | NULL |
++------+------+
+```

docs/sql-manual/sql-functions/table-functions/json-each-text.md

@@ -0,0 +1,99 @@
+---
+{
+    "title": "JSON_EACH_TEXT",
+    "language": "en",
+    "description": "Expands the top-level JSON object into a set of key/value pairs, where the value column is returned as plain text. Must be used with LATERAL VIEW."
+}
+---
+
+## Description
+
+The `json_each_text` table function expands the top-level JSON object into a set of key/value pairs. Each row contains one key (`key`) and its corresponding value (`value`). Unlike [`json_each`](json-each.md), the `value` column is of type TEXT, so string values are returned **without** JSON quotes.
+
+Must be used with [`LATERAL VIEW`](../../../query-data/lateral-view.md).
+
+## Syntax
+
+```sql
+JSON_EACH_TEXT(<json_str>)
+```
+
+## Parameters
+
+| Parameter    | Description                                          |
+| ------------ | ---------------------------------------------------- |
+| `<json_str>` | The JSON string to expand. The content must be a JSON object. |
+
+## Return Value
+
+Returns multi-column, multi-row data. Each row corresponds to one key-value pair in the JSON object:
+
+| Column  | Type | Description                                                                          |
+|---------|------|--------------------------------------------------------------------------------------|
+| `key`   | TEXT | The key name from the JSON object                                                     |
+| `value` | TEXT | The corresponding value as plain text (string values have no quotes, e.g. `foo`) |
+
+Special cases:
+- If `<json_str>` is NULL, returns 0 rows
+- If `<json_str>` is an empty object (`{}`), returns 0 rows
+- A JSON `null` value is returned as SQL `NULL`
+
+## Examples
+
+Basic usage: expand a JSON object with string values
+
+```sql
+SELECT k, v
+FROM (SELECT 1) dummy
+LATERAL VIEW json_each_text('{"a":"foo","b":"bar"}') t AS k, v;
+```
+
+```text
++---+-----+
+| k | v   |
++---+-----+
+| a | foo |
+| b | bar |
++---+-----+
+```
+
+> The `value` column is of TEXT type, so string values have **no** JSON quotes (unlike `json_each`).
+
+JSON object with multiple value types
+
+```sql
+SELECT k, v
+FROM (SELECT 1) dummy
+LATERAL VIEW json_each_text('{"str":"hello","num":42,"bool":true,"null_val":null}') t AS k, v;
+```
+
+```text
++----------+-------+
+| k        | v     |
++----------+-------+
+| str      | hello |
+| num      | 42    |
+| bool     | true  |
+| null_val | NULL  |
++----------+-------+
+```
+
+> JSON `null` values map to SQL `NULL`.
+
+NULL parameter: returns 0 rows
+
+```sql
+SELECT k, v
+FROM (SELECT 1) dummy
+LATERAL VIEW json_each_text(NULL) t AS k, v;
+-- Empty set
+```
+
+Empty object: returns 0 rows
+
+```sql
+SELECT k, v
+FROM (SELECT 1) dummy
+LATERAL VIEW json_each_text('{}') t AS k, v;
+-- Empty set
+```

docs/sql-manual/sql-functions/table-functions/json-each.md

@@ -0,0 +1,97 @@
+---
+{
+    "title": "JSON_EACH",
+    "language": "en",
+    "description": "Expands the top-level JSON object into a set of key/value pairs, where the value column retains JSON type. Must be used with LATERAL VIEW."
+}
+---
+
+## Description
+
+The `json_each` table function expands the top-level JSON object into a set of key/value pairs. Each row contains one key (`key`) and its corresponding value (`value`). The `value` column retains the JSON type, so string values are returned with JSON quotes preserved.
+
+Must be used with [`LATERAL VIEW`](../../../query-data/lateral-view.md).
+
+## Syntax
+
+```sql
+JSON_EACH(<json_str>)
+```
+
+## Parameters
+
+| Parameter    | Description                                          |
+| ------------ | ---------------------------------------------------- |
+| `<json_str>` | The JSON string to expand. The content must be a JSON object. |
+
+## Return Value
+
+Returns multi-column, multi-row data. Each row corresponds to one key-value pair in the JSON object:
+
+| Column  | Type   | Description                                                                 |
+|---------|--------|-----------------------------------------------------------------------------|
+| `key`   | String | The key name from the JSON object                                           |
+| `value` | JSON   | The corresponding value, kept as JSON type (string values include quotes, e.g. `"foo"`) |
+
+Special cases:
+- If `<json_str>` is NULL, returns 0 rows
+- If `<json_str>` is an empty object (`{}`), returns 0 rows
+
+## Examples
+
+Basic usage: expand a JSON object with string values
+
+```sql
+SELECT k, v
+FROM (SELECT 1) dummy
+LATERAL VIEW json_each('{"a":"foo","b":"bar"}') t AS k, v;
+```
+
+```text
++---+-------+
+| k | v     |
++---+-------+
+| a | "foo" |
+| b | "bar" |
++---+-------+
+```
+
+> The `value` column is of JSON type, so string values retain their JSON quotes.
+
+JSON object with multiple value types
+
+```sql
+SELECT k, v
+FROM (SELECT 1) dummy
+LATERAL VIEW json_each('{"str":"hello","num":42,"bool":true,"null_val":null,"arr":[1,2]}') t AS k, v;
+```
+
+```text
++----------+---------+
+| k        | v       |
++----------+---------+
+| str      | "hello" |
+| num      | 42      |
+| bool     | true    |
+| null_val | NULL    |
+| arr      | [1,2]   |
++----------+---------+
+```
+
+NULL parameter: returns 0 rows
+
+```sql
+SELECT k, v
+FROM (SELECT 1) dummy
+LATERAL VIEW json_each(NULL) t AS k, v;
+-- Empty set
+```
+
+Empty object: returns 0 rows
+
+```sql
+SELECT k, v
+FROM (SELECT 1) dummy
+LATERAL VIEW json_each('{}') t AS k, v;
+-- Empty set
+```