transform: METADATA and METADATA (#2216)

Author: BohuTANG

docs/en/guides/40-load-data/04-transform/00-querying-parquet.md

@@ -65,12 +65,12 @@ FROM @parquet_query_stage
 ```
 ### Query with Metadata
 
-Query Parquet files directly from a stage, including metadata columns like `metadata$filename` and `metadata$file_row_number`:
+Query Parquet files directly from a stage, including metadata columns like `METADATA$FILENAME` and `METADATA$FILE_ROW_NUMBER`:
 
 ```sql
 SELECT
-    metadata$filename AS file,
-    metadata$file_row_number AS row,
+    METADATA$FILENAME,
+    METADATA$FILE_ROW_NUMBER,
     *
 FROM @parquet_query_stage
 (

docs/en/guides/40-load-data/04-transform/01-querying-csv.md

@@ -81,12 +81,12 @@ FROM @csv_query_stage
 ```
 ### Query with Metadata
 
-Query CSV files directly from a stage, including metadata columns like `metadata$filename` and `metadata$file_row_number`:
+Query CSV files directly from a stage, including metadata columns like `METADATA$FILENAME` and `METADATA$FILE_ROW_NUMBER`:
 
 ```sql
 SELECT
-    metadata$filename AS file,
-    metadata$file_row_number AS row,
+    METADATA$FILENAME,
+    METADATA$FILE_ROW_NUMBER,
     $1, $2, $3
 FROM @csv_query_stage
 (

docs/en/guides/40-load-data/04-transform/02-querying-tsv.md

@@ -80,12 +80,12 @@ FROM @tsv_query_stage
 ```
 ### Query with Metadata
 
-Query TSV files directly from a stage, including metadata columns like `metadata$filename` and `metadata$file_row_number`:
+Query TSV files directly from a stage, including metadata columns like `METADATA$FILENAME` and `METADATA$FILE_ROW_NUMBER`:
 
 ```sql
 SELECT
-    metadata$filename AS file,
-    metadata$file_row_number AS row,
+    METADATA$FILENAME,
+    METADATA$FILE_ROW_NUMBER,
     $1, $2, $3
 FROM @tsv_query_stage
 (

docs/en/guides/40-load-data/04-transform/03-querying-ndjson.md

@@ -78,12 +78,12 @@ FROM @ndjson_query_stage
 ```
 ### Query with Metadata
 
-Query NDJSON files directly from a stage, including metadata columns like `metadata$filename` and `metadata$file_row_number`:
+Query NDJSON files directly from a stage, including metadata columns like `METADATA$FILENAME` and `METADATA$FILE_ROW_NUMBER`:
 
 ```sql
 SELECT
-    metadata$filename AS file,
-    metadata$file_row_number AS row,
+    METADATA$FILENAME,
+    METADATA$FILE_ROW_NUMBER,
     $1:title, $1:author
 FROM @ndjson_query_stage
 (

docs/en/guides/40-load-data/04-transform/03-querying-orc.md

@@ -87,12 +87,12 @@ FROM
 
 ### Query with Metadata
 
-Query ORC files directly from a stage, including metadata columns like `metadata$filename` and `metadata$file_row_number`:
+Query ORC files directly from a stage, including metadata columns like `METADATA$FILENAME` and `METADATA$FILE_ROW_NUMBER`:
 
 ```sql
 SELECT
-    metadata$filename AS file,
-    metadata$file_row_number AS row,
+    METADATA$FILENAME,
+    METADATA$FILE_ROW_NUMBER,
     *
 FROM @orc_query_stage
 (

docs/en/guides/40-load-data/04-transform/04-querying-avro.md

@@ -36,7 +36,7 @@ Databend provides comprehensive support for querying Avro files directly from st
 
 *   **Variant Representation**: Each row in an Avro file is treated as a variant, referenced by `$1`. This allows for flexible access to nested structures within the Avro data.
 *   **Type Mapping**: Each Avro type is mapped to a corresponding variant type in Databend.
-*   **Metadata Access**: You can access metadata columns like `metadata$filename` and `metadata$file_row_number` for additional context about the source file and row.
+*   **Metadata Access**: You can access metadata columns like `METADATA$FILENAME` and `METADATA$FILE_ROW_NUMBER` for additional context about the source file and row.
 
 ## Tutorial
 
@@ -95,12 +95,12 @@ FROM @avro_query_stage
 
 ### Query with Metadata
 
-Query Avro files directly from a stage, including metadata columns like `metadata$filename` and `metadata$file_row_number`:
+Query Avro files directly from a stage, including metadata columns like `METADATA$FILENAME` and `METADATA$FILE_ROW_NUMBER`:
 
 ```sql
 SELECT
-    metadata$filename AS file,
-    metadata$file_row_number AS row,
+    METADATA$FILENAME,
+    METADATA$FILE_ROW_NUMBER,
     CAST($1:id AS INT) AS id,
     $1:name AS name
 FROM @avro_query_stage

docs/en/guides/40-load-data/04-transform/04-querying-metadata.md

@@ -7,8 +7,8 @@ The following file-level metadata fields are available for the supported file fo
 
 | File Metadata              | Type    | Description                                      |
 | -------------------------- | ------- | ------------------------------------------------ |
-| `metadata$filename`        | VARCHAR | The name of the file from which the row was read |
-| `metadata$file_row_number` | INT     | The row number within the file (starting from 0) |
+| `METADATA$FILENAME`        | VARCHAR | The name of the file from which the row was read |
+| `METADATA$FILE_ROW_NUMBER` | INT     | The row number within the file (starting from 0) |
 
 These metadata fields are available in: