array_first
array_first
array_first
description
Returns the first element in the array for which func(arr1[i]) returns something other than 0.
Syntax
T array_first(lambda, ARRAY<T>)
Use a lambda bool expression and an array as the input parameters, the lambda expression is used to evaluate the internal data of other input ARRAY parameters.
notice
Only supported in vectorized engine
example
mysql> select array_first(x->x>2, [1,2,3,0]) ;
+------------------------------------------------------------------------------------------------+
| array_first(array_filter(ARRAY(1, 2, 3, 0), array_map([x] -> x(0) > 2, ARRAY(1, 2, 3, 0))), -1) |
+------------------------------------------------------------------------------------------------+
| 3 |
+------------------------------------------------------------------------------------------------+
mysql> select array_first(x->x>4, [1,2,3,0]) ;
+------------------------------------------------------------------------------------------------+
| array_first(array_filter(ARRAY(1, 2, 3, 0), array_map([x] -> x(0) > 4, ARRAY(1, 2, 3, 0))), -1) |
+------------------------------------------------------------------------------------------------+
| NULL |
+------------------------------------------------------------------------------------------------+
mysql> select array_first(x->x>1, [1,2,3,0]) ;
+---------------------------------------------------------------------------------------------+
| array_first(array_filter(ARRAY(1, 2, 3, 0), array_map([x] -> x > 1, ARRAY(1, 2, 3, 0))), 1) |
+---------------------------------------------------------------------------------------------+
| 2 |
+---------------------------------------------------------------------------------------------+
keywords
ARRAY, LAST, array_first
