| --- | |
| { | |
| "title": "ARRAY_PUSHBACK", | |
| "language": "en-US", | |
| "description": "Adds an element to the end of an array. The function returns a new array containing all elements from the original array plus the newly added element." | |
| } | |
| --- | |
| ## array_pushback | |
| <version since="2.0.0"> | |
| </version> | |
| ## Description | |
| Adds an element to the end of an array. The function returns a new array containing all elements from the original array plus the newly added element. | |
| ## Alias | |
| - array_append | |
| ## Syntax | |
| ```sql | |
| array_pushback(ARRAY<T> arr, T element) | |
| ``` | |
| ### Parameters | |
| - `arr`:ARRAY<T> type, the array to which to add an element | |
| - `element`:T type, the element to add to the end of the array | |
| **Supported types for T:** | |
| - Numeric types: TINYINT, SMALLINT, INT, BIGINT, LARGEINT, FLOAT, DOUBLE, DECIMAL | |
| - String types: CHAR, VARCHAR, STRING | |
| - Date and time types: DATE, DATETIME, DATEV2, DATETIMEV2, TIMESTAMP_NS | |
| - Boolean type: BOOLEAN | |
| - IP types: IPV4, IPV6 | |
| - UUID: [UUID](../../../basic-element/sql-data-types/uuid.md) | |
| - Complex types: ARRAY, MAP, STRUCT | |
| ### Return Value | |
| Return type: ARRAY<T> | |
| Return value meaning: | |
| - Returns a new array containing all elements from the original array plus the newly added element | |
| - NULL: if the input array is NULL | |
| Usage notes: | |
| - The function adds the specified element to the end of the array | |
| - Empty arrays can add elements normally, the new element type needs to be compatible with the array element type | |
| - For null values in array elements: null elements are handled normally | |
| **Query Examples:** | |
| Add an element to the end of a string array: | |
| ```sql | |
| SELECT array_pushback(['apple', 'banana', 'cherry'], 'date'); | |
| +----------------------------------------------------+ | |
| | array_pushback(['apple', 'banana', 'cherry'], 'date') | | |
| +----------------------------------------------------+ | |
| | ["apple", "banana", "cherry", "date"] | | |
| +----------------------------------------------------+ | |
| ``` | |
| Add a null element to the end of an array containing null values: | |
| ```sql | |
| SELECT array_pushback([1, null, 3], null); | |
| +------------------------------------+ | |
| | array_pushback([1, null, 3], null) | | |
| +------------------------------------+ | |
| | [1, null, 3, null] | | |
| +------------------------------------+ | |
| ``` | |
| Add an element to the end of an empty array: | |
| ```sql | |
| SELECT array_pushback([], 42); | |
| +--------------------------+ | |
| | array_pushback([], 42) | | |
| +--------------------------+ | |
| | [42] | | |
| +--------------------------+ | |
| ``` | |
| Add an element to the end of a float array: | |
| ```sql | |
| SELECT array_pushback([1.1, 2.2, 3.3], 4.4); | |
| +------------------------------------------+ | |
| | array_pushback([1.1, 2.2, 3.3], 4.4) | | |
| +------------------------------------------+ | |
| | [1.1, 2.2, 3.3, 4.4] | | |
| +------------------------------------------+ | |
| ``` | |
| NULL arrays return NULL: | |
| ```sql | |
| SELECT array_pushback(NULL, 1); | |
| +--------------------------+ | |
| | array_pushback(NULL, 1) | | |
| +--------------------------+ | |
| | NULL | | |
| +--------------------------+ | |
| ``` | |
| Add an element to the end of an IP address array: | |
| ```sql | |
| SELECT array_pushback(CAST(['192.168.1.1', '192.168.1.2'] AS ARRAY<IPV4>), CAST('192.168.1.3' AS IPV4)); | |
| +----------------------------------------------------------------------------------+ | |
| | array_pushback(CAST(['192.168.1.1', '192.168.1.2'] AS ARRAY<IPV4>), CAST('192.168.1.3' AS IPV4)) | | |
| +----------------------------------------------------------------------------------+ | |
| | ["192.168.1.1", "192.168.1.2", "192.168.1.3"] | | |
| +----------------------------------------------------------------------------------+ | |
| ``` | |
| Add an element to the end of a nested array: | |
| ```sql | |
| SELECT array_pushback([[1,2], [3,4]], [5,6]); | |
| +------------------------------------------+ | |
| | array_pushback([[1,2], [3,4]], [5,6]) | | |
| +------------------------------------------+ | |
| | [[1, 2], [3, 4], [5, 6]] | | |
| +------------------------------------------+ | |
| ``` | |
| Add an element to the end of a MAP array: | |
| ```sql | |
| SELECT array_pushback([{'a':1}, {'b':2}], {'c':3}); | |
| +----------------------------------------------+ | |
| | array_pushback([{'a':1}, {'b':2}], {'c':3}) | | |
| +----------------------------------------------+ | |
| | [{"a":1}, {"b":2}, {"c":3}] | | |
| +----------------------------------------------+ | |
| ``` | |
| Add an element to the end of a STRUCT array: | |
| ```sql | |
| SELECT array_pushback(array(named_struct('name','Alice','age',20), named_struct('name','Bob','age',30)), named_struct('name','Charlie','age',40)); | |
| +-------------------------------------------------------------------------------------------------------------------------------------------+ | |
| | array_pushback(array(named_struct('name','Alice','age',20), named_struct('name','Bob','age',30)), named_struct('name','Charlie','age',40)) | | |
| +-------------------------------------------------------------------------------------------------------------------------------------------+ | |
| | [{"name":"Alice", "age":20}, {"name":"Bob", "age":30}, {"name":"Charlie", "age":40}] | | |
| +-------------------------------------------------------------------------------------------------------------------------------------------+ | |
| ``` | |
| Error with wrong number of parameters: | |
| ```sql | |
| SELECT array_pushback([1,2,3]); | |
| ERROR 1105 (HY000): errCode = 2, detailMessage: Can not found function 'array_pushback' which has 1 arity. Candidate functions are: [array_pushback(Expression, Expression)] | |
| ``` | |
| Error when passing non-array types: | |
| ```sql | |
| SELECT array_pushback('not_an_array', 1); | |
| ERROR 1105 (HY000): errCode = 2, detailMessage: Can not find the compatibility function signature: array_pushback(VARCHAR(12), TINYINT) | |
| ``` | |
| ### Keywords | |
| ARRAY, PUSHBACK, ARRAY_PUSHBACK |