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array_exists

array_exists

array_exists(lambda,array1,array2....) array_exists(array1)

description

Syntax

BOOLEAN array_exists(lambda, ARRAY<T> arr1, ARRAY<T> arr2, ... )
BOOLEAN array_exists(ARRAY<T> arr)

使用一个可选 lambda 表达式作为输入参数,对其他的输入 ARRAY 参数的内部数据做对应表达式计算。当计算返回非 0 时,返回 1;否则返回 0。 在 lambda 表达式中输入的参数为 1 个或多个,必须和后面的输入 array 列数量一致。在 lambda 中可以执行合法的标量函数,不支持聚合函数等。 在没有使用 lambda 作为参数时,array1 作为计算结果。

array_exists(x->x, array1);
array_exists(x->(x%2 = 0), array1);
array_exists(x->(abs(x)-1), array1);
array_exists((x,y)->(x = y), array1, array2);
array_exists(array1);

example


mysql [test]>select *, array_exists(x->x>1,[1,2,3]) from array_test2 order by id;
+------+-----------------+-------------------------+-----------------------------------------------+
| id | c_array1 | c_array2 | array_exists([x] -> x(0) > 1, ARRAY(1, 2, 3)) |
+------+-----------------+-------------------------+-----------------------------------------------+
| 1 | [1, 2, 3, 4, 5] | [10, 20, -40, 80, -100] | [0, 1, 1] |
| 2 | [6, 7, 8] | [10, 12, 13] | [0, 1, 1] |
| 3 | [1] | [-100] | [0, 1, 1] |
| 4 | NULL | NULL | [0, 1, 1] |
+------+-----------------+-------------------------+-----------------------------------------------+
4 rows in set (0.02 sec)

mysql [test]>select c_array1, c_array2, array_exists(x->x%2=0,[1,2,3]) from array_test2 order by id;
+-----------------+-------------------------+---------------------------------------------------+
| c_array1 | c_array2 | array_exists([x] -> x(0) % 2 = 0, ARRAY(1, 2, 3)) |
+-----------------+-------------------------+---------------------------------------------------+
| [1, 2, 3, 4, 5] | [10, 20, -40, 80, -100] | [0, 1, 0] |
| [6, 7, 8] | [10, 12, 13] | [0, 1, 0] |
| [1] | [-100] | [0, 1, 0] |
| NULL | NULL | [0, 1, 0] |
+-----------------+-------------------------+---------------------------------------------------+
4 rows in set (0.02 sec)

mysql [test]>select c_array1, c_array2, array_exists(x->abs(x)-1,[1,2,3]) from array_test2 order by id;
+-----------------+-------------------------+----------------------------------------------------+
| c_array1 | c_array2 | array_exists([x] -> abs(x(0)) - 1, ARRAY(1, 2, 3)) |
+-----------------+-------------------------+----------------------------------------------------+
| [1, 2, 3, 4, 5] | [10, 20, -40, 80, -100] | [0, 1, 1, 1, 1] |
| [6, 7, 8] | [10, 12, 13] | [1, 1, 1] |
| [1, NULL] | [-100] | [0, NULL] |
| NULL | NULL | NULL |
+-----------------+-------------------------+----------------------------------------------------+
4 rows in set (0.02 sec)

mysql [test]>select c_array1, c_array2, array_exists((x,y)->x>y,c_array1,c_array2) from array_test2 order by id;
+-----------------+-------------------------+-------------------------------------------------------------+
| c_array1 | c_array2 | array_exists([x, y] -> x(0) > y(1), `c_array1`, `c_array2`) |
+-----------------+-------------------------+-------------------------------------------------------------+
| [1, 2, 3, 4, 5] | [10, 20, -40, 80, -100] | [0, 0, 1, 0, 1] |
| [6, 7, 8] | [10, 12, 13] | [0, 0, 0] |
| [1] | [-100] | [1] |
| NULL | NULL | NULL |
+-----------------+-------------------------+-------------------------------------------------------------+
4 rows in set (0.02 sec)

mysql [test]>select *, array_exists(c_array1) from array_test2 order by id;
+------+-----------------+-------------------------+--------------------------+
| id | c_array1 | c_array2 | array_exists(`c_array1`) |
+------+-----------------+-------------------------+--------------------------+
| 1 | [1, 2, 3, 0, 5] | [10, 20, -40, 80, -100] | [1, 1, 1, 0, 1] |
| 2 | [6, 7, 8] | [10, 12, 13] | [1, 1, 1] |
| 3 | [0, NULL] | [-100] | [0, NULL] |
| 4 | NULL | NULL | NULL |
+------+-----------------+-------------------------+--------------------------+
4 rows in set (0.02 sec)

keywords

ARRAY,ARRAY_EXISTS