Name
is_before — Returns true if the given entity is before the second given entity in document order, otherwise returns false.
Synopsis
boolean
is_before
(
|
ent1 entity , |
ent2
entity
); |
Description
The function ensures that both ent1 and
ent2 are XML entities and the returns true if
ent1 and ent2 are both in
the same XML document and ent1 is strictly before
ent2 in document order. It returns false if one of
them is not an entity but an empty node-set or if their documents differ
or if they're equal or if one of them is an ancestor of other or if
ent1 is simply after ent2 in
document order.
Parameters
ent1
An XML entity or an node-set whose first node is compared.
ent2
An XML entity or an node-set whose first node is compared.
Return Types
Boolean
Errors
Table 24.139. Errors signalled by is_before()
| SQLState | Error Code | Error Text | Description |
|---|---|---|---|
| XP001 | XPFB0 | First argument of XPATH function is-after() or is-before() must be XML entity | The value that is neither an XML entity nor an empty node-set may not be compared using document order. |
| XP001 | XPFB1 | Second argument of XPATH function is-after() or is-before() must be XML entity | The value that is neither an XML entity nor an empty node-set may not be compared using document order. |
Examples
Example 24.635.
Find all chapters that have table of content before title
/book/chapter[is-before(title,toc)]