Overview#
The virtual list view (VLV) is a supportedControl that can be attached to a searchRequest to use a server-side sorting control.Virtual List View Control may be combined with the simple paged results control the search Request also include the server-side sort control to ensure that the results are consistently sorted across requests.
The VLV control is defined in draft-ietf-ldapext-ldapv3-vlv
.
As far as we can determine this is NOT an approved standard.
The request control has an OID of 2.16.840.1.113730.3.4.9 and the value is encoded as follows:
VirtualListViewRequest ::= SEQUENCE {
beforeCount INTEGER (0..maxInt),
afterCount INTEGER (0..maxInt),
target CHOICE {
byOffset [0] SEQUENCE {
offset INTEGER (1 .. maxInt),
contentCount INTEGER (0 .. maxInt) },
greaterThanOrEqual [1] AssertionValue },
contextID OCTET STRING OPTIONAL }
The response control has an OID of 2.16.840.1.113730.3.4.10 and the value is encoded as:
VirtualListViewResponse ::= SEQUENCE {
targetPosition INTEGER (0 .. maxInt),
contentCount INTEGER (0 .. maxInt),
virtualListViewResult ENUMERATED {
success (0),
operationsError (1),
protocolError (3),
unwillingToPerform (53),
insufficientAccessRights (50),
timeLimitExceeded (3),
adminLimitExceeded (11),
innapropriateMatching (18),
sortControlMissing (60),
offsetRangeError (61),
other(80),
... },
contextID OCTET STRING OPTIONAL }
Virtual List View Control Example#
To Search Using the Virtual List View Control The sort order option (-S) must be used with the Virtual List View control. This example uses the Virtual List View Control options to specify the following:- Before=0*. Specifies that 0 entries before the target should be displayed.
- After=2*. Specifies that 2 entries after the target should be displayed.
- Index=1*. Specifies that the offset of the target entry within the result set be returned.
- Count=0*. Specifies that target entry at the index position be returned, which is the first entry.
This example is from the OpenDS LDAPSEARCH utility (Other LDAP vendors tools may vary)
ldapsearch -h localhost -p 1389 -D "cn=Directory Manager" -w bindPassword -b dc=example,dc=com --searchScope sub --sortOrder givenName --virtualListView "0:2:1:0" "(objectclass=*)"
The same only for OpenLDAP (at least used to work)
ldapsearch -h localhost -p 1389 -D "cn=Directory Manager" -w bindPassword -b dc=example,dc=com --searchScope sub -S givenName -x -G "0:2:1:0" "(objectclass=*) givenName"
To find the first two entries where givenName starts with "j" (OpenLDAP)
- Before=0*. Specifies that 0 entries before the target should be displayed.
- After=2*. Specifies that 2 entries after the target should be displayed.
- "j" for entries where givenName begins with "j"
ldapsearch -h localhost -p 1389 -D "cn=Directory Manager" -w bindPassword -b dc=example,dc=com --searchScope sub -S givenName -x -G "0:4:j" "(objectclass=*) givenName"
