alamb commented on code in PR #13102: URL: https://github.com/apache/datafusion/pull/13102#discussion_r1817386600
########## docs/source/user-guide/sql/special_functions.md: ########## @@ -0,0 +1,94 @@ +<!--- + Licensed to the Apache Software Foundation (ASF) under one + or more contributor license agreements. See the NOTICE file + distributed with this work for additional information + regarding copyright ownership. The ASF licenses this file + to you under the Apache License, Version 2.0 (the + "License"); you may not use this file except in compliance + with the License. You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, + software distributed under the License is distributed on an + "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY + KIND, either express or implied. See the License for the + specific language governing permissions and limitations + under the License. +--> + +# Special Functions + +## Expansion Functiions + +- [unnest](#unnest) +- [unnest(struct)](#unnest-struct) + +### `unnest` + +Expands an array or map into rows. + +#### Arguments + +- **array**: Array expression to unnest. + Can be a constant, column, or function, and any combination of array operators. + +#### Examples + +``` +> select unnest(make_array(1, 2, 3, 4, 5)); ++------------------------------------------------------------------+ +| unnest(make_array(Int64(1),Int64(2),Int64(3),Int64(4),Int64(5))) | ++------------------------------------------------------------------+ +| 1 | +| 2 | +| 3 | +| 4 | +| 5 | ++------------------------------------------------------------------+ +``` + +``` +> select unnest(range(0, 10)); ++-----------------------------------+ +| unnest(range(Int64(0),Int64(10))) | ++-----------------------------------+ +| 0 | +| 1 | +| 2 | +| 3 | +| 4 | +| 5 | +| 6 | +| 7 | +| 8 | +| 9 | ++-----------------------------------+ +``` + +### `unnest (struct)` + +Unwraps struct fields into columns. + +#### Arguments + +- **struct**: Object expression to unnest. + Can be a constant, column, or function, and any combination of object operators. + +#### Examples + +``` +> select * from foo; ++---------------------+ +| column1 | Review Comment: Good idea --done in 777f58de9 -- 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. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
