| --- |
| { |
| "title": "STRUCT", |
| "language": "en" |
| } |
| --- |
| |
| ## struct() |
| |
| :::tip Tips |
| This function is supported since the Apache Doris 2.0 version |
| ::: |
| |
| struct() |
| |
| |
| |
| ### description |
| |
| #### Syntax |
| |
| `STRUCT<T1, T2, T3, ...> struct(T1, T2, T3, ...)` |
| |
| construct an struct with variadic elements and return it, Tn could be column or literal |
| |
| ### example |
| |
| ``` |
| mysql> select struct(1, 'a', "abc"); |
| +-----------------------+ |
| | struct(1, 'a', 'abc') | |
| +-----------------------+ |
| | {1, 'a', 'abc'} | |
| +-----------------------+ |
| 1 row in set (0.03 sec) |
| |
| mysql> select struct(null, 1, null); |
| +-----------------------+ |
| | struct(NULL, 1, NULL) | |
| +-----------------------+ |
| | {NULL, 1, NULL} | |
| +-----------------------+ |
| 1 row in set (0.02 sec) |
| |
| mysql> select struct(cast('2023-03-16' as datetime)); |
| +----------------------------------------+ |
| | struct(CAST('2023-03-16' AS DATETIME)) | |
| +----------------------------------------+ |
| | {2023-03-16 00:00:00} | |
| +----------------------------------------+ |
| 1 row in set (0.01 sec) |
| |
| mysql> select struct(k1, k2, null) from test_tb; |
| +--------------------------+ |
| | struct(`k1`, `k2`, NULL) | |
| +--------------------------+ |
| | {1, 'a', NULL} | |
| +--------------------------+ |
| 1 row in set (0.04 sec) |
| ``` |
| |
| ### keywords |
| |
| STRUCT,CONSTRUCTOR |