Used to define the merge keys on which the input sequences of a merging operation are sorted.
Permitted parent elements: xsl:merge-source
The merge key can be defined either by a string expression in a select attribute, or by an enclosed sequence constructor.
Declares the algorithm used for alphabetic
collating, as an ISO language code such as
Declares the sort order; the default is
Declares the collation, by the name of a collating sequence.
Relevant only for
Declares whether collating is based on
alphabetic sequence or numeric sequence. The permitted values are either
Available in XSLT 3.0. From Saxon 9.8, available in all editions. Implemented in Saxon-PE and Saxon-EE since Saxon 9.6. Available for all platforms.
The syntax and semantics of an
xsl:merge-key element are closely
based on the rules for the xsl:sort
element (the only exception being the absence of the
attribute); the difference is that
xsl:merge-key elements do not
cause a sort to take place, they merely declare the existing sort order of the
For details and examples, see xsl:merge.