Detect Null Values

Functions isNull or hasNull detect NULL values. isNull returns a scalar or a vector depending on the input data; hasNull always returns 0 or 1 indicating if an object contains at least one NULL value.

$ isNull(00i);
1

$ isNull(-128c);
1
// the minimum char is reserved for NULL value

$ isNull(1 NULL 2);
[0,1,0]

$ hasNull(1 NULL 2);
1