docs: add parquet.case_insensitive parameter for file sources

ingestion/formats-and-encoding-options.mdx

@@ -265,7 +265,9 @@ When using a file source to read Parquet files, the schema must be defined accor
 | `timestamp(_, None)`    | timestamp    |
 
 <Note>
-Parquet sources require case-sensitive column names. However, PostgreSQL converts unquoted column names to lowercase by default. To preserve case sensitivity when defining the schema, use double quotes around column names.
+By default, Parquet sources require case-sensitive column name matching. However, PostgreSQL converts unquoted column names to lowercase by default. To preserve case sensitivity when defining the schema, use double quotes around column names.
+
+Alternatively, you can set `parquet.case_insensitive = 'true'` in the source connector options to enable case-insensitive column matching. This allows you to use lowercase column names in your schema (e.g., `id`, `name`) even when the Parquet file has mixed-case column names (e.g., `ID`, `Name`). If multiple columns match case-insensitively, the match is ambiguous and ignored.
 </Note>
 
 ## Parameter reference

integrations/sources/azure-blob.mdx

@@ -41,6 +41,7 @@ FORMAT data_format ENCODE data_encode (
 | azblob.endpoint\_url             | **Required**. The URL of the Azure Blob Storage service endpoint.                                                                                                                                                                                                |
 | match\_pattern                   | **Conditional**. Set to find object keys in `azblob.container_name` that match the given pattern. Standard Unix-style [glob](https://en.wikipedia.org/wiki/Glob%5F%28programming%29) syntax is supported. A typical usage follows the `prefix/*.suffix` pattern. For example, `your_directory/*.parquet` matches all Parquet files under `your_directory/`. If `match_pattern` does not contain `/`, the scan runs from the container root. |
 | compression\_format              | **Optional**. Specifies the compression format of the file being read. When set to gzip or gz, the file reader reads all files with the `.gz` suffix; when set to `None` or not defined, the file reader will automatically read and decompress `.gz` and `.gzip` files. |
+| parquet.case\_insensitive              | **Optional**. For Parquet files only. When set to `true`, enables case-insensitive column name matching. This is useful when the Parquet file has column names with different casing than your table schema (e.g., `ID` in the file, `id` in the table). If multiple columns match case-insensitively, the match is ambiguous and ignored. Default is `false`. |
 
 ### Other parameters
 
@@ -145,6 +146,25 @@ WITH (
     azblob.endpoint_url = 'xxx',
     match_pattern = '*.parquet',
 ) FORMAT PLAIN ENCODE PARQUET;
+```
+
+To handle Parquet files with mixed-case column names (e.g., `ID`, `Name`, `Age`), use the `parquet.case_insensitive` option:
+
+```sql Example with case-insensitive matching
+CREATE SOURCE s2(
+    id int,
+    name varchar,
+    age int
+)
+WITH (
+    connector = 'azblob',
+    azblob.container_name = 'xxx',
+    azblob.credentials.account_name = 'xxx',
+    azblob.credentials.account_key = 'xxx',
+    azblob.endpoint_url = 'xxx',
+    match_pattern = '*.parquet',
+    parquet.case_insensitive = 'true'
+) FORMAT PLAIN ENCODE PARQUET;
 ```
     </Tab>
 </Tabs>

integrations/sources/google-cloud-storage.mdx

@@ -39,6 +39,7 @@ FORMAT data_format ENCODE data_encode (
 | match\_pattern       | **Conditional**. This field is used to find object keys in the bucket that match the given pattern. Standard Unix-style [glob](https://en.wikipedia.org/wiki/Glob%5F%28programming%29) syntax is supported. A typical usage follows the `prefix/*.suffix` pattern. For example, `your_directory/*.parquet` matches all Parquet files under `your_directory/`. If `match_pattern` does not contain `/`, the scan runs from the container root. |
 | compression\_format  | **Optional**. This field specifies the compression format of the file being read. You can define `compression_format` in the CREATE TABLE statement. When set to gzip or gz, the file reader reads all files with the `.gz` suffix. When set to None or not defined, the file reader will automatically read and decompress `.gz` and `.gzip` files.   |
 | refresh.interval.sec       | **Optional**. Configure the time interval between operations of listing files. It determines the delay in discovering new files, with a default value of 60 seconds.   |
+| parquet.case\_insensitive       | **Optional**. For Parquet files only. When set to `true`, enables case-insensitive column name matching. This is useful when the Parquet file has column names with different casing than your table schema (e.g., `ID` in the file, `id` in the table). If multiple columns match case-insensitively, the match is ambiguous and ignored. Default is `false`.   |
 
 ### Other parameters
 
@@ -141,8 +142,25 @@ CREATE TABLE t(
 WITH (
     connector = 'gcs',
     gcs.bucket_name = 'example-bucket',
-    gcs.credential = 'xxxxx'
+    gcs.credential = 'xxxxx',
+    match_pattern = '*.parquet'
+) FORMAT PLAIN ENCODE PARQUET;
+```
+
+To handle Parquet files with mixed-case column names (e.g., `ID`, `Name`, `Age`), use the `parquet.case_insensitive` option:
+
+```sql Example with case-insensitive matching
+CREATE TABLE t(
+    id int,
+    name varchar,
+    age int
+)
+WITH (
+    connector = 'gcs',
+    gcs.bucket_name = 'example-bucket',
+    gcs.credential = 'xxxxx',
     match_pattern = '*.parquet',
+    parquet.case_insensitive = 'true'
 ) FORMAT PLAIN ENCODE PARQUET;
 ```
     </Tab>

integrations/sources/s3.mdx

@@ -52,6 +52,7 @@ For CSV data, specify the delimiter in the `delimiter` option in `ENCODE propert
 | `match_pattern`        | **Conditional**. This field is used to find object keys in `s3.bucket_name` that match the given pattern. Standard Unix-style [glob](https://en.wikipedia.org/wiki/Glob%5F%28programming%29) syntax is supported. A typical usage follows the `prefix/*.suffix` pattern. For example, `your_directory/*.parquet` matches all Parquet files under `your_directory/`. If `match_pattern` does not contain `/`, the scan runs from the container root. |
 | `s3.assume_role`       | **Optional**. Specifies the ARN of an IAM role to assume when accessing S3\. It allows temporary, secure access to S3 resources without sharing long-term credentials.                                                                                                                                                                        |
 | `refresh.interval.sec`       | **Optional**. Configure the time interval between operations of listing files. It determines the delay in discovering new files, with a default value of 60 seconds.                                                                                                                                                                        |
+| `parquet.case_insensitive`       | **Optional**. For Parquet files only. When set to `true`, enables case-insensitive column name matching. This is useful when the Parquet file has column names with different casing than your table schema (e.g., `ID` in the file, `id` in the table). If multiple columns match case-insensitively, the match is ambiguous and ignored. Default is `false`.                                                                                                                                                                        |
 
 <Note>
 In RisingWave Cloud, the default AWS credential provider chain is disabled. Provide `s3.credentials.access` and `s3.credentials.secret` (or use a supported assume-role setup). These credentials cannot be omitted. The `enable_config_load` option is supported only in self-hosted deployments.
@@ -153,6 +154,25 @@ WITH (
     s3.credentials.secret = 'xxxxx'
 ) FORMAT PLAIN ENCODE PARQUET;
 
+```
+
+To handle Parquet files with mixed-case column names (e.g., `ID`, `Name`, `Age`), use the `parquet.case_insensitive` option:
+
+```sql Example with case-insensitive matching
+CREATE TABLE s(
+    id int,
+    name varchar,
+    age int
+)
+WITH (
+    connector = 's3_v2',
+    match_pattern = '*.parquet',
+    s3.region_name = 'ap-southeast-2',
+    s3.bucket_name = 'example-s3-source',
+    s3.credentials.access = 'xxxxx',
+    s3.credentials.secret = 'xxxxx',
+    parquet.case_insensitive = 'true'
+) FORMAT PLAIN ENCODE PARQUET;
 ```
   </Tab>
 </Tabs>