ISCHILDOF
Syntax
<ischildof-expression> := 'ISCHILDOF(' <Key> ',' <Key> { ',' <Key> } ')'
Since
1.2
Return-type
Boolean
Description
This function checks whether all keys from the first argument are equal to or children of at least one of the keys from the second argument.
A key A is child of a key B, if:
- B is the direct parent of A,
- or the parent of A is a child of B
If more than two arguments are passed, all keys of the first arguments must be a child of at least one key of all following arguments
If one of the arguments is NULL, the function returns NULL. If the first argument is empty and contains no key, the function returns TRUE.
Examples
ISCHILDOF( Time:'Jan/2003', Time:'2003' )
= TRUE
ISCHILDOF( Time:'2003', Time:'Jan/2003' )
= FALSE
ISCHILDOF( Time:'2003', NULL )
= NULL
ISCHILDOF( NULL, Time:'Jan/2003' )
= NULL
See also
ISPARENTOF
