If-None-Match
E204878
If-None-Match is an HTTP request header used for conditional requests, typically with ETags, to perform cache validation or conditional updates without unnecessarily transferring data.
All labels observed (1)
| Label | Occurrences |
|---|---|
| If-None-Match canonical | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T1817417 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
NED1
Entity disambiguation (via context triple)
gpt-5-mini-2025-08-07
Target entity: If-None-Match Context triple: [RFC 7232, definesHeaderField, If-None-Match]
-
A.
Retry-After
Retry-After is an HTTP response header that tells clients how long to wait before making another request, typically used with status codes like 429 or 503 to indicate a temporary condition.
-
B.
Difference Engine
The Difference Engine is an early mechanical calculator designed by Charles Babbage to automatically compute and tabulate polynomial functions, often regarded as a precursor to modern computers.
-
C.
If/Then
If/Then is a contemporary Broadway musical that follows a woman’s parallel life paths in New York City, featuring a pop-influenced score and a starring role for Idina Menzel.
-
D.
Does Not Suffice
"Does Not Suffice" is a song by Joanna Newsom from her 2010 album *Have One on Me*, noted for its intimate piano arrangement and emotionally raw, narrative lyrics.
-
E.
Without Equal
"Without Equal" is the English motto expressing the unmatched excellence and elite status of the U.S. Army Special Operations Command.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
NED2
Entity disambiguation (via description)
gpt-5-mini-2025-08-07
Target entity: If-None-Match Target entity description: If-None-Match is an HTTP request header used for conditional requests, typically with ETags, to perform cache validation or conditional updates without unnecessarily transferring data.
-
A.
Retry-After
Retry-After is an HTTP response header that tells clients how long to wait before making another request, typically used with status codes like 429 or 503 to indicate a temporary condition.
-
B.
Difference Engine
The Difference Engine is an early mechanical calculator designed by Charles Babbage to automatically compute and tabulate polynomial functions, often regarded as a precursor to modern computers.
-
C.
If/Then
If/Then is a contemporary Broadway musical that follows a woman’s parallel life paths in New York City, featuring a pop-influenced score and a starring role for Idina Menzel.
-
D.
Does Not Suffice
"Does Not Suffice" is a song by Joanna Newsom from her 2010 album *Have One on Me*, noted for its intimate piano arrangement and emotionally raw, narrative lyrics.
-
E.
Without Equal
"Without Equal" is the English motto expressing the unmatched excellence and elite status of the U.S. Army Special Operations Command.
- F. None of above. chosen
Statements (46)
| Predicate | Object |
|---|---|
| instanceOf |
HTTP request header field
ⓘ
conditional request header ⓘ |
| applicableTo | selected representation of the target resource ⓘ |
| avoids | unnecessary data transfer ⓘ |
| cacheBenefit |
reduces bandwidth usage
ⓘ
reduces server load ⓘ |
| canUseWeakETags | yes ⓘ |
| clientRequirement | client must store ETag from previous response ⓘ |
| comparisonRule | condition is true if none of the listed ETags match the current ETag ⓘ |
| comparisonType | strong comparison by default ⓘ |
| conditionBasis | entity tag comparison ⓘ |
| definedIn | RFC 7232 ⓘ |
| effectOnGET | enables conditional retrieval based on ETag ⓘ |
| effectOnPUT | prevents overwriting when resource state already matches given ETag ⓘ |
| headerType | request header ⓘ |
| operatesOn | current ETag of the resource ⓘ |
| primaryPurpose |
cache validation
ⓘ
conditional updates ⓘ |
| relatedHeader |
ETag
ⓘ
If-Match ⓘ If-Modified-Since ⓘ |
| replacesSpecification | RFC 2616 section on conditional requests ⓘ |
| responseStatusOnMatchGET | 304 Not Modified ⓘ |
| responseStatusOnMatchUnsafe | 412 Precondition Failed ⓘ |
| securityConsideration | can help avoid lost updates when used with ETags ⓘ |
| serverBehaviorOnMatch |
may reject state-changing requests with 412 Precondition Failed
ⓘ
may return 304 Not Modified for GET or HEAD ⓘ |
| serverBehaviorOnNoMatch | processes request normally ⓘ |
| supportsValue |
multiple ETags
ⓘ
single ETag ⓘ wildcard * ⓘ |
| syntaxExample |
If-None-Match: "etag1", "etag2"
ⓘ
If-None-Match: "etagvalue" ⓘ If-None-Match: * ⓘ |
| typicalUseCase |
RESTful APIs for conditional updates
ⓘ
web browsers validating cached resources ⓘ |
| usedFor |
client cache revalidation
ⓘ
optimistic concurrency control ⓘ |
| usedInMethod |
DELETE
ⓘ
GET ⓘ HEAD ⓘ PUT ⓘ other safe and unsafe HTTP methods ⓘ |
| usedInProtocol | HTTP ⓘ |
| usedWith | ETag header ⓘ |
| wildcardSemantics | * matches any current representation ⓘ |
How these facts were elicited
The pipeline generated the facts above by prompting gpt-5.1 with this entity's name + description and the instruction below.
Instruction
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Input
Subject: If-None-Match Description of subject: If-None-Match is an HTTP request header used for conditional requests, typically with ETags, to perform cache validation or conditional updates without unnecessarily transferring data.
Referenced by (1)
Full triples — surface form annotated when it differs from this entity's canonical label.