Alias: ARRAY_CAT Combines one or more arrays that are passed as arguments.

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Syntax

ARRAY_CONCAT(<array> [, ...n])
—OR— 
<expression> || <expression>

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Parameters

ParameterDescriptionSupported input types
<array> [, ...n]The arrays to be combined. If only one array is given, an identical array is returned.ARRAY

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|| operator

ParameterDescriptionSupported input types
<expression>The expressions to be concatenated.TEXT / ARRAY, but at least one ARRAY
To enable array concatenation, one parameter to the || operator must be of type ARRAY, while the other parameter can be a string whose value can be converted to the underlying type of the array parameter, or it can be an array of the same type. If one parameter to the || operator is NULL, the result will be the non-null parameter; if both parameters are NULL, the result will be NULL. The concatenation operator || can also be used for string concatenation.

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Return Type

ARRAY of the same type as the input arrays

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Example

In the following example, two arrays are combined to show all of the levels in a particular game: 
SELECT
    ARRAY_CONCAT([ 1, 2, 3, 4 ], [ 5, 6, 7, 8, 9, 10 ]) AS levels;
Returns: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] The following example concatenates two integer arrays: 
SELECT ARRAY[1,2] || ARRAY[3];
Returns: [1, 2, 3] The following example concatenates a string, whose value can be converted to integer, with an integer array: 
SELECT '{2}' || ARRAY[1];
Returns: [2, 1]