Update ingestion/overview.mdx

Co-authored-by: congyi wang <[email protected]>
Signed-off-by: IrisWan <[email protected]>

ingestion/overview.mdx

@@ -144,7 +144,7 @@ SELECT count(*) from s3_source;
 
 ### Data type mapping in Parquet
 
-You can use the table function `file_scan()` to read Parquet files from sources. Below is the data type mapping that shows how RisingWave converts data types from file sources in Parquet format.
+When using file source to read parquet files, please define the schema information according to the following mapping.
 
 | File source type | RisingWave type |
 | :----------- | :-------------- |