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STRUCT

struct()

提示

该功能自 Apache Doris 2.0 版本起支持

struct()

description

Syntax

STRUCT<T1, T2, T3, ...> struct(T1, T2, T3, ...)

根据给定的值构造并返回 struct,参数可以是多列或常量

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