Github user xccui commented on a diff in the pull request:
https://github.com/apache/flink/pull/4894#discussion_r147582469
--- Diff:
flink-libraries/flink-table/src/main/scala/org/apache/flink/table/sources/CsvTableSource.scala
---
@@ -38,23 +38,26 @@ import scala.collection.mutable
* @param path The path to the CSV file.
* @param fieldNames The names of the table fields.
* @param fieldTypes The types of the table fields.
+ * @param selectedFields The fields which will be read and returned by
the table source.
+ * If None, all fields are returned.
* @param fieldDelim The field delimiter, "," by default.
* @param rowDelim The row delimiter, "\n" by default.
* @param quoteCharacter An optional quote character for String values,
null by default.
* @param ignoreFirstLine Flag to ignore the first line, false by default.
* @param ignoreComments An optional prefix to indicate comments, null by
default.
* @param lenient Flag to skip records with parse error instead to fail,
false by default.
*/
-class CsvTableSource(
+class CsvTableSource private (
private val path: String,
private val fieldNames: Array[String],
private val fieldTypes: Array[TypeInformation[_]],
- private val fieldDelim: String =
CsvInputFormat.DEFAULT_FIELD_DELIMITER,
- private val rowDelim: String = CsvInputFormat.DEFAULT_LINE_DELIMITER,
- private val quoteCharacter: Character = null,
- private val ignoreFirstLine: Boolean = false,
- private val ignoreComments: String = null,
- private val lenient: Boolean = false)
+ private val selectedFields: Array[Int],
+ private val fieldDelim: String,
+ private val rowDelim: String,
+ private val quoteCharacter: Character,
+ private val ignoreFirstLine: Boolean,
+ private val ignoreComments: String,
+ private val lenient: Boolean)
extends BatchTableSource[Row]
--- End diff --
Maybe we need a base class instead of traits to do something like checking
the equality of numbers of field names/types.
---
