array_map(lambda,array,....)
ARRAY<T> array_map(lambda, ARRAY<T> array1, ARRAY<T> array2)
Use a lambda expression as the input parameter to calculate the corresponding expression for the internal data of other input ARRAY parameters. The number of parameters entered in the lambda expression is 1 or more, which must be consistent with the number of input array columns. The scalar functions can be executed in lambda, and aggregate functions are not supported.
array_map(x->x, array1); array_map(x->(x+2), array1); array_map(x->(abs(x)-2), array1); array_map((x,y)->(x = y), array1, array2); array_map((x,y)->(power(x,2)+y), array1, array2); array_map((x,y,z)->(abs(x)+y*z), array1, array2, array3);
mysql [test]>select *, array_map(x->x,[1,2,3]) from array_test2 order by id; +------+-----------------+-------------------------+----------------------------------------+ | id | c_array1 | c_array2 | array_map([x] -> x(0), ARRAY(1, 2, 3)) | +------+-----------------+-------------------------+----------------------------------------+ | 1 | [1, 2, 3, 4, 5] | [10, 20, -40, 80, -100] | [1, 2, 3] | | 2 | [6, 7, 8] | [10, 12, 13] | [1, 2, 3] | | 3 | [1] | [-100] | [1, 2, 3] | | 4 | NULL | NULL | [1, 2, 3] | +------+-----------------+-------------------------+----------------------------------------+ 4 rows in set (0.02 sec) mysql [test]>select *, array_map(x->x+2,[1,2,3]) from array_test2 order by id; +------+-----------------+-------------------------+--------------------------------------------+ | id | c_array1 | c_array2 | array_map([x] -> x(0) + 2, ARRAY(1, 2, 3)) | +------+-----------------+-------------------------+--------------------------------------------+ | 1 | [1, 2, 3, 4, 5] | [10, 20, -40, 80, -100] | [3, 4, 5] | | 2 | [6, 7, 8] | [10, 12, 13] | [3, 4, 5] | | 3 | [1] | [-100] | [3, 4, 5] | | 4 | NULL | NULL | [3, 4, 5] | +------+-----------------+-------------------------+--------------------------------------------+ 4 rows in set (0.02 sec) mysql [test]>select c_array1, c_array2, array_map(x->x,[1,2,3]) from array_test2 order by id; +-----------------+-------------------------+----------------------------------------+ | c_array1 | c_array2 | array_map([x] -> x(0), ARRAY(1, 2, 3)) | +-----------------+-------------------------+----------------------------------------+ | [1, 2, 3, 4, 5] | [10, 20, -40, 80, -100] | [1, 2, 3] | | [6, 7, 8] | [10, 12, 13] | [1, 2, 3] | | [1] | [-100] | [1, 2, 3] | | NULL | NULL | [1, 2, 3] | +-----------------+-------------------------+----------------------------------------+ 4 rows in set (0.01 sec) mysql [test]>select c_array1, c_array2, array_map(x->power(x,2),[1,2,3]) from array_test2 order by id; +-----------------+-------------------------+----------------------------------------------------+ | c_array1 | c_array2 | array_map([x] -> power(x(0), 2.0), ARRAY(1, 2, 3)) | +-----------------+-------------------------+----------------------------------------------------+ | [1, 2, 3, 4, 5] | [10, 20, -40, 80, -100] | [1, 4, 9] | | [6, 7, 8] | [10, 12, 13] | [1, 4, 9] | | [1] | [-100] | [1, 4, 9] | | NULL | NULL | [1, 4, 9] | +-----------------+-------------------------+----------------------------------------------------+ mysql [test]>select c_array1, c_array2, array_map((x,y)->x+y,c_array1,c_array2) from array_test2 order by id; +-----------------+-------------------------+----------------------------------------------------------+ | c_array1 | c_array2 | array_map([x, y] -> x(0) + y(1), `c_array1`, `c_array2`) | +-----------------+-------------------------+----------------------------------------------------------+ | [1, 2, 3, 4, 5] | [10, 20, -40, 80, -100] | [11, 22, -37, 84, -95] | | [6, 7, 8] | [10, 12, 13] | [16, 19, 21] | | [1] | [-100] | [-99] | | NULL | NULL | NULL | +-----------------+-------------------------+----------------------------------------------------------+ 4 rows in set (0.02 sec) mysql [test]>select c_array1, c_array2, array_map((x,y)->power(x,2)+y,c_array1, c_array2) from array_test2 order by id; +-----------------+-------------------------+----------------------------------------------------------------------+ | c_array1 | c_array2 | array_map([x, y] -> power(x(0), 2.0) + y(1), `c_array1`, `c_array2`) | +-----------------+-------------------------+----------------------------------------------------------------------+ | [1, 2, 3, 4, 5] | [10, 20, -40, 80, -100] | [11, 24, -31, 96, -75] | | [6, 7, 8] | [10, 12, 13] | [46, 61, 77] | | [1] | [-100] | [-99] | | NULL | NULL | NULL | +-----------------+-------------------------+----------------------------------------------------------------------+ 4 rows in set (0.03 sec) mysql [test]>select *,array_map(x->x=3,c_array1) from array_test2 order by id; +------+-----------------+-------------------------+----------------------------------------+ | id | c_array1 | c_array2 | array_map([x] -> x(0) = 3, `c_array1`) | +------+-----------------+-------------------------+----------------------------------------+ | 1 | [1, 2, 3, 4, 5] | [10, 20, -40, 80, -100] | [0, 0, 1, 0, 0] | | 2 | [6, 7, 8] | [10, 12, 13] | [0, 0, 0] | | 3 | [1] | [-100] | [0] | | 4 | NULL | NULL | NULL | +------+-----------------+-------------------------+----------------------------------------+ 4 rows in set (0.02 sec) mysql [test]>select *,array_map(x->x>3,c_array1) from array_test2 order by id; +------+-----------------+-------------------------+----------------------------------------+ | id | c_array1 | c_array2 | array_map([x] -> x(0) > 3, `c_array1`) | +------+-----------------+-------------------------+----------------------------------------+ | 1 | [1, 2, 3, 4, 5] | [10, 20, -40, 80, -100] | [0, 0, 0, 1, 1] | | 2 | [6, 7, 8] | [10, 12, 13] | [1, 1, 1] | | 3 | [1] | [-100] | [0] | | 4 | NULL | NULL | NULL | +------+-----------------+-------------------------+----------------------------------------+ 4 rows in set (0.02 sec) mysql [test]>select *,array_map((x,y)->x>y,c_array1,c_array2) from array_test2 order by id; +------+-----------------+-------------------------+----------------------------------------------------------+ | id | c_array1 | c_array2 | array_map([x, y] -> x(0) > y(1), `c_array1`, `c_array2`) | +------+-----------------+-------------------------+----------------------------------------------------------+ | 1 | [1, 2, 3, 4, 5] | [10, 20, -40, 80, -100] | [0, 0, 1, 0, 1] | | 2 | [6, 7, 8] | [10, 12, 13] | [0, 0, 0] | | 3 | [1] | [-100] | [1] | | 4 | NULL | NULL | NULL | +------+-----------------+-------------------------+----------------------------------------------------------+ 4 rows in set (0.02 sec) mysql [test]>select array_map(x->cast(x as string), c_array1) from test_array_map_function; +-----------------+-------------------------------------------------------+ | c_array1 | array_map([x] -> CAST(x(0) AS CHARACTER), `c_array1`) | +-----------------+-------------------------------------------------------+ | [1, 2, 3, 4, 5] | ['1', '2', '3', '4', '5'] | | [6, 7, 8] | ['6', '7', '8'] | | [] | [] | | NULL | NULL | +-----------------+-------------------------------------------------------+ 4 rows in set (0.01 sec)
ARRAY,MAP,ARRAY_MAP