array_with_constant

SinceVersion 1.2.0

array_with_constant array_repeat

description

Syntax

  1. ARRAY<T> array_with_constant(n, T)
  2. ARRAY<T> array_repeat(T, n)

返回一个数组, 包含n个重复的T常量。array_repeat与array_with_constant功能相同，用来兼容hive语法格式。

notice

仅支持向量化引擎中使用

example

  1. mysql> set enable_vectorized_engine=true;
  3. mysql> select array_with_constant(2, "hello"), array_repeat("hello", 2);
  4. +---------------------------------+--------------------------+
  5. | array_with_constant(2, 'hello') | array_repeat('hello', 2) |
  6. +---------------------------------+--------------------------+
  7. | ['hello', 'hello']              | ['hello', 'hello']       |
  8. +---------------------------------+--------------------------+
  9. 1 row in set (0.04 sec)
  11. mysql> select array_with_constant(3, 12345), array_repeat(12345, 3);
  12. +-------------------------------+------------------------+
  13. | array_with_constant(3, 12345) | array_repeat(12345, 3) | 
  14. +-------------------------------+------------------------+
  15. | [12345, 12345, 12345]         | [12345, 12345, 12345]  |
  16. +-------------------------------+------------------------+
  17. 1 row in set (0.01 sec)
  19. mysql> select array_with_constant(3, null), array_repeat(null, 3);
  20. +------------------------------+-----------------------+
  21. | array_with_constant(3, NULL) | array_repeat(NULL, 3) |
  22. +------------------------------+-----------------------+
  23. | [NULL, NULL, NULL]           |  [NULL, NULL, NULL]   |
  24. +------------------------------+-----------------------+
  25. 1 row in set (0.01 sec)
  27. mysql> select array_with_constant(null, 3), array_repeat(3, null);
  28. +------------------------------+-----------------------+
  29. | array_with_constant(NULL, 3) | array_repeat(3, NULL) |
  30. +------------------------------+-----------------------+
  31. | []                           | []                    |
  32. +------------------------------+-----------------------+
  33. 1 row in set (0.01 sec)

keywords

ARRAY,WITH_CONSTANT,ARRAY_WITH_CONSTANT,ARRAY_REPEAT