dianfu commented on a change in pull request #8057: [FLINK-12028][table] Add `addColumns`,`renameColumns`, `dropColumns` … URL: https://github.com/apache/flink/pull/8057#discussion_r269882661
########## File path: flink-table/flink-table-api-java/src/main/java/org/apache/flink/table/api/Table.java ########## @@ -879,4 +879,118 @@ * @return An OverWindowedTable to specify the aggregations. */ OverWindowedTable window(OverWindow... overWindows); + + /** + * Performs a field add operation. Similar to an SQL SELECT statement. The field expressions + * can contain complex expressions, but can not contain aggregations. It will throw an exception + * if the added fields already exist. + * + * <p>Example: + * <pre> + * {@code + * tab.addColumns("a + 1 as a1, concat(b, 'sunny') as b1") + * } + * </pre> + */ + Table addColumns(String fields); + + /** + * Performs a field add operation. Similar to an SQL SELECT statement. The field expressions + * can contain complex expressions, but can not contain aggregations. It will throw an exception + * if the added fields already exist. + * + * <p>Scala Example: + * + * <pre> + * {@code + * tab.addColumns('a + 1 as 'a1, concat('b, "sunny") as 'b1) + * } + * </pre> + */ + Table addColumns(Expression... fields); + + /** + * Performs a field add operation. Similar to an SQL SELECT statement. The field expressions + * can contain complex expressions, but can not contain aggregations. Existing fields will be + * replaced if {@code replaceIfExist} is true. If the added fields have duplicate field name, + * then the last one is valid. + * + * <p>Example: + * <pre> + * {@code + * tab.addColumns(true, "a + 1 as a1, concat(b, 'sunny') as b1") + * } + * </pre> + */ + Table addColumns(boolean replaceIfExist, String fields); + + /** + * Performs a field add operation. Similar to an SQL SELECT statement. The field expressions + * can contain complex expressions, but can not contain aggregations. Existing fields will be + * replaced if {@code replaceIfExist} is true. If the added fields have duplicate field name, + * then the last one is valid. + * + * <p>Scala Example: + * <pre> + * {@code + * tab.addColumns(true, 'a + 1 as 'a1, concat('b, "sunny") as 'b1) + * } + * </pre> + */ + Table addColumns(boolean replaceIfExist, Expression... fields); + + /** + * Performs a field rename operation. Similar to an field alias statement. The field expressions + * should be alias expressions, and only the existing fields can be renamed. + * + * <p>Example: + * + * <pre> + * {@code + * tab.renameColumns("a as a1, b as b1") + * } + * </pre> + */ + Table renameColumns(String fields); + + /** + * Performs a field rename operation. Similar to an field alias statement. The field expressions + * should be alias expressions, and only the existing fields can be renamed. + * + * <p>Scala Example: + * + * <pre> + * {@code + * tab.renameColumns('a as 'a1, 'b as 'b1) + * } + * </pre> + */ + Table renameColumns(Expression... fields); + + /** + * Performs a field drop operation. The field expressions + * should be an field reference expressions, and only existing fields can be dropped. Review comment: remove "an" ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services