The Sort Context Set (version 1.0)
Index Modifiers Examples Indexes/Relations/etc.
- The sort context set defines a set of index modifiers to be used within a sortby clause
- The URI for this context set is: info:srw/cql-context-set/1/sort-v1.0
- The recommended short name is: sort
Note that CQL does not permit index modifiers, except within a sort clause.
For example in the CQL query: "author=wolfe sortby title" 'sortby title' is a sort clause; 'title' is an index. 'author', which is the primary index of query, may not have a modifier, but 'title', which is the index of the sort clause, may. Thus for example, in the CQL query: "author=wolfe sortby title/ascending" 'ascending' is an index modifier.
Index Modifiers
Modifier |
Description |
ignoreCase |
Case-insensitive sorting: for example, unit and UNIT sort together. |
respectCase |
Case-sensitive sorting: for example, unit and UNIT sort separately. |
ignoreAccents |
Accent-insensitive sorting: for example sorensen and sørensen sort together. |
respectAccents |
Accent-sensitive sorting: for example sorensen and sørensen sort separately. |
ascending |
Sort in ascending order. |
descending |
Sort in descending order. |
missingOmit |
Records that have no value for the specified index are omitted from the sorted result set. |
missingFail |
Records that have no value for the specified index cause the search/sort operation to fail with the diagnostic info:srw/diagnostic/1/93 |
missingLow |
Records that have no value for the specified index are treated as if they had the lowest possible value, so that they sort first in ascending order and last in descending order. |
missingHigh |
Records that have no value for the specified index are treated as if they had the highest possible value. |
missingValue=value |
Records that have no value for the specified index are treated as if they had the specified value. |
locale=value |
Sort according to the specified locale, which will in general include specifications for whether sorting is case-sensitive or insensitive, how it treats accents, etc. The value is usually of the form C, french, fr_CH, fr_CH.iso88591 or similar. |
unicodeCollate=value |
Specfies the Unicode collation level. The value should be a small integer as described in the Unicode Collation Algorithm report at www.unicode.org/reports/tr10 |
Examples
- dc.creator=plews sortby dc.title/sort.respectCase
Sort by title, case sensitive
- dc.creator=plews sortby dc.title/sort.respectCase/sort.descending
Sort case sensitive and in descending order
- dc.creator=plews sortby dc.date/sort.missingOmit
Sort by date: records that have no date field are omitted from the result set.
- dc.creator=plews sortby dc.date/sort.missingValue=1970
Sort by date: records that have no date field are sorted as though
they had a date of 1970.
Indexes
No indexes are defined for this context set.
Relations
No relations are defined for this context set.
Relation Modifiers
No relation modifiers are defined for this context set.
Relation Qualifiers
No relation qualifiers are defined for this context set.
Boolean Modifiers
No boolean modifiers are defined for this context set.