huaxingao commented on a change in pull request #28196: [SPARK-31428][SQL][DOCS] Document Common Table Expression in SQL Reference URL: https://github.com/apache/spark/pull/28196#discussion_r407279058
########## File path: docs/sql-ref-syntax-qry-select-cte.md ########## @@ -19,4 +19,120 @@ license: | limitations under the License. --- -**This page is under construction** +### Description + +A common table expression (CTE) defines a temporary result set that a user can reference within the duration of a SQL statement. A CTE can be used wherever a SELECT statement is used; for example, it can be used in a SELECT, INSERT, UPDATE, DELETE, MERGE or CREATE VIEW statement. A CTE has a name with an optional column names list, followed by a query expression. When a CTE references itself, it is called a recursive CTE. Review comment: I guess maybe only mention the SELECT? ```A common table expression (CTE) defines a temporary result set that a user can reference possibly multiple times within the scope of a SQL statement. A CTE is used mainly in a SELECT statement. It is defined with a name including an optional column names list, followed by a query expression. When a CTE references itself, it is called a recursive CTE.``` Does this look OK to you? ---------------------------------------------------------------- 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: [email protected] With regards, Apache Git Services --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
