ARRAY

ARRAY

is a data type used to represent a value composed of a sequence of elements of the same type. This data type can store a series of elements sharing the same data type, making it convenient for unified management and operations.

Syntax

ARRAY <elementType>

• elementType

  elementType
  : Specifies the data type of the elements in the array.

ARRAY Constant Format

select [1,3,4];

This format represents an array constant. When defining an array constant, do not use quotes, because quotes will cause it to be recognized as a string type, and the string

'[1,3,4]'

cannot be directly converted to

array<int>

type using

CAST

.

Examples

1. Create an integer array:

   SELECT ARRAY(1, 2, 3);

   Result:

   result
   [1, 2, 3]

2. Convert an integer array to a string array:

   SELECT CAST(ARRAY(1, 2, 3) AS ARRAY<STRING>);

   Result:

   result
   ["1", "2", "3"]

3. Get the data type of array elements:

   SELECT typeof(ARRAY(1.2, 1.4, 1.8));

   Result:

   result
   array<decimal(2,1)>

4. Create a nested array (an array containing other arrays):

   SELECT CAST(ARRAY(ARRAY(10, 20), ARRAY(30, 40)) AS ARRAY<ARRAY<DECIMAL(10,2)>>);

   Result:

   result
   [[10.00, 20.00], [30.00, 40.00]]

5. Get a specific element from an array:

   SELECT a[0] FROM VALUES(ARRAY(10, 20, 30)) AS T(a);

   Result:

   result
   10

6. Use

   ARRAY_CONTAINS

   ARRAY_CONTAINS
   to check if a specific element exists in an array:

   SELECT array_contains(ARRAY(1, 2, 3),3);

   Result:

   Result
   true

7. Sort an array:

   SELECT ARRAY_SORT(array(2, 1, 3));

   Result:

   result
   [1, 2, 3]

8. Merge two arrays:

   SELECT array_union(array(2, 1, 3, 3), array(3, 5));

   Result:

   result
   [2,1,3,5]