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MAP

描述

使用若干组键值对构造一个特定类型的 Map<K, V>

语法

MAP( <key1> , <value1> [, <key2>,<value2> ... ])

参数

参数说明
<key>构造 map 的 key
<value>构造 map 的 value

返回值

返回由若干组键值对构造的特定类型 Map<K, V>

举例

select map(1, "100", 0.1, 2),map(1, "100", 0.1, 2)[1];
+---------------------------------------------------------------------------------------+-------------------------------------------------------------------------------------------------------------------------------+
| map(cast(1 as DECIMALV3(2, 1)), '100', cast(0.1 as DECIMALV3(2, 1)), cast(2 as TEXT)) | element_at(map(cast(1 as DECIMALV3(2, 1)), '100', cast(0.1 as DECIMALV3(2, 1)), cast(2 as TEXT)), cast(1 as DECIMALV3(2, 1))) |
+---------------------------------------------------------------------------------------+-------------------------------------------------------------------------------------------------------------------------------+
| {1.0:"100", 0.1:"2"} | 100 |
+---------------------------------------------------------------------------------------+-------------------------------------------------------------------------------------------------------------------------------+