3 ms·

FQL: A KV Query Language

79 points by surprisetalk 2y ago

MarkMarine 2y ago
I don’t have any exposure to foundationDB except for the incredible endorsement of Aphyr saying they have a test suite so good he didn’t bother testing it with jepson. I’m shocked by the demo I just saw with FQL, when I hear KV store I assume I can only query by Key. This looks far richer. I’m not sure I understand what I’m seeing, can anyone actually using this DB explain?
- rapsey 2y ago
  FDB is a sorted KV database. So you can do range queries.
- thadt 2y ago
  You can only query by key (and key ranges). To work with the fact that FoundationDB just exposes keys as raw bytes, the FDB team developed a rather clever 'tuple' serialization protocol and standardized its presence in the different client bindings. This encoding lets developers turn a tuple of values into byte string that sort correctly, making them useful for creating indexes and other higher level layers such as directories. This library appears to be a nice CLI interface to working with those facilities. Unless you were using these tools (tuples and directories) on top of another KV store, this query language probably wouldn't help much elsewhere. However, the tuple encoding scheme is rather straightforward and for doesn't depend on anything specific to FDB (aside from versionstamps but you just wouldn't implement those for another DB).
  - fakpods 2y ago
    [flagged]
  - withinboredom 2y ago
    Versions are super important on any kv store that deals with concurrency. Without it, you can’t do any kind of concurrency control.
mdaniel 2y ago
I dunno why you chose to editorialize the repo's summary (and thus the html title contents) away from the much clearer "Foundation DB Query Language" than what sounded like a generic KV query language whose readme launched right into talking about Foundation DB and never got around to any S3 specifics
- surprisetalk 2y ago
  Totally fair point. Although FQL is specifically designed for FoundationDB, I'm personally excited about using it as a generic syntax for querying other KV stores.
  - fakpods 2y ago
    [flagged]
cryptonector 2y ago
Every NoSQL ends up getting a QL.
- josephg 2y ago
  NoSQL != NoQL.
  - fakpods 2y ago
    [flagged]
- PittleyDunkin 2y ago
  "NoSQL" was always a terribly-named movement indicating a heinously-shallow view of data stores.
- otabdeveloper4 2y ago
  SQL is "Structured Query Language". So yes, they get the QL without the S.
geogra4 2y ago
Reminds me a lot of XPath/XQuery
m3047 2y ago
I was looking for possible inspiration for some kind of best practice to reduce the amount of information returned for wildcarded Redis queries (reduce it to just what's changing, or maybe some piece of what's changing). Didn't find it. Could be the documentation lacks clarity.
fatnoah 2y ago
Am I the only one that thought of this? https://en.wikipedia.org/wiki/Facebook_Query_Language https://en.wikipedia.org/wiki/Facebook_Query_Language
- janderland 2y ago
  There is also Fauna Query Language. I gave up on choosing a unique name. https://fauna.com/product/fql https://fauna.com/product/fql

79 points by surprisetalk 2y ago

I don’t have any exposure to foundationDB except for the incredible endorsement of Aphyr saying they have a test suite so good he didn’t bother testing it with jepson. I’m shocked by the demo I just saw with FQL, when I hear KV store I assume I can only query by Key. This looks far richer. I’m not sure I understand what I’m seeing, can anyone actually using this DB explain?

rapsey 2y ago
FDB is a sorted KV database. So you can do range queries.
thadt 2y ago
You can only query by key (and key ranges). To work with the fact that FoundationDB just exposes keys as raw bytes, the FDB team developed a rather clever 'tuple' serialization protocol and standardized its presence in the different client bindings. This encoding lets developers turn a tuple of values into byte string that sort correctly, making them useful for creating indexes and other higher level layers such as directories. This library appears to be a nice CLI interface to working with those facilities. Unless you were using these tools (tuples and directories) on top of another KV store, this query language probably wouldn't help much elsewhere. However, the tuple encoding scheme is rather straightforward and for doesn't depend on anything specific to FDB (aside from versionstamps but you just wouldn't implement those for another DB).
- fakpods 2y ago
  [flagged]
- withinboredom 2y ago
  Versions are super important on any kv store that deals with concurrency. Without it, you can’t do any kind of concurrency control.

mdaniel 2y ago

I dunno why you chose to editorialize the repo's summary (and thus the html title contents) away from the much clearer "Foundation DB Query Language" than what sounded like a generic KV query language whose readme launched right into talking about Foundation DB and never got around to any S3 specifics

surprisetalk 2y ago
Totally fair point. Although FQL is specifically designed for FoundationDB, I'm personally excited about using it as a generic syntax for querying other KV stores.
- fakpods 2y ago
  [flagged]

cryptonector 2y ago

Every NoSQL ends up getting a QL.

josephg 2y ago
NoSQL != NoQL.
- fakpods 2y ago
  [flagged]
PittleyDunkin 2y ago
"NoSQL" was always a terribly-named movement indicating a heinously-shallow view of data stores.
otabdeveloper4 2y ago
SQL is "Structured Query Language". So yes, they get the QL without the S.

geogra4 2y ago

Reminds me a lot of XPath/XQuery

m3047 2y ago

I was looking for possible inspiration for some kind of best practice to reduce the amount of information returned for wildcarded Redis queries (reduce it to just what's changing, or maybe some piece of what's changing). Didn't find it. Could be the documentation lacks clarity.

fatnoah 2y ago

Am I the only one that thought of this? https://en.wikipedia.org/wiki/Facebook_Query_Language https://en.wikipedia.org/wiki/Facebook_Query_Language

janderland 2y ago
There is also Fauna Query Language. I gave up on choosing a unique name. https://fauna.com/product/fql https://fauna.com/product/fql