mentat/tests/query.rs
2017-11-30 15:03:04 -08:00

757 lines
28 KiB
Rust

// Copyright 2016 Mozilla
//
// Licensed under the Apache License, Version 2.0 (the "License"); you may not use
// this file except in compliance with the License. You may obtain a copy of the
// License at http://www.apache.org/licenses/LICENSE-2.0
// Unless required by applicable law or agreed to in writing, software distributed
// under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
// CONDITIONS OF ANY KIND, either express or implied. See the License for the
// specific language governing permissions and limitations under the License.
extern crate chrono;
extern crate time;
extern crate mentat;
extern crate mentat_core;
extern crate mentat_db;
extern crate mentat_query_algebrizer; // For errors.
use std::str::FromStr;
use chrono::FixedOffset;
use mentat_core::{
TypedValue,
ValueType,
Utc,
Uuid,
};
use mentat::{
NamespacedKeyword,
PlainSymbol,
QueryInputs,
QueryResults,
Variable,
new_connection,
q_once,
};
use mentat::conn::Conn;
use mentat::errors::{
Error,
ErrorKind,
};
#[test]
fn test_rel() {
let mut c = new_connection("").expect("Couldn't open conn.");
let db = mentat_db::db::ensure_current_version(&mut c).expect("Couldn't open DB.");
// Rel.
let start = time::PreciseTime::now();
let results = q_once(&c, &db.schema,
"[:find ?x ?ident :where [?x :db/ident ?ident]]", None)
.expect("Query failed");
let end = time::PreciseTime::now();
// This will need to change each time we add a default ident.
assert_eq!(39, results.len());
// Every row is a pair of a Ref and a Keyword.
if let QueryResults::Rel(ref rel) = results {
for r in rel {
assert_eq!(r.len(), 2);
assert!(r[0].matches_type(ValueType::Ref));
assert!(r[1].matches_type(ValueType::Keyword));
}
} else {
panic!("Expected rel.");
}
println!("{:?}", results);
println!("Rel took {}µs", start.to(end).num_microseconds().unwrap());
}
#[test]
fn test_failing_scalar() {
let mut c = new_connection("").expect("Couldn't open conn.");
let db = mentat_db::db::ensure_current_version(&mut c).expect("Couldn't open DB.");
// Scalar that fails.
let start = time::PreciseTime::now();
let results = q_once(&c, &db.schema,
"[:find ?x . :where [?x :db/fulltext true]]", None)
.expect("Query failed");
let end = time::PreciseTime::now();
assert_eq!(0, results.len());
if let QueryResults::Scalar(None) = results {
} else {
panic!("Expected failed scalar.");
}
println!("Failing scalar took {}µs", start.to(end).num_microseconds().unwrap());
}
#[test]
fn test_scalar() {
let mut c = new_connection("").expect("Couldn't open conn.");
let db = mentat_db::db::ensure_current_version(&mut c).expect("Couldn't open DB.");
// Scalar that succeeds.
let start = time::PreciseTime::now();
let results = q_once(&c, &db.schema,
"[:find ?ident . :where [24 :db/ident ?ident]]", None)
.expect("Query failed");
let end = time::PreciseTime::now();
assert_eq!(1, results.len());
if let QueryResults::Scalar(Some(TypedValue::Keyword(ref rc))) = results {
// Should be '24'.
assert_eq!(&NamespacedKeyword::new("db.type", "keyword"), rc.as_ref());
assert_eq!(24,
db.schema.get_entid(rc).unwrap());
} else {
panic!("Expected scalar.");
}
println!("{:?}", results);
println!("Scalar took {}µs", start.to(end).num_microseconds().unwrap());
}
#[test]
fn test_tuple() {
let mut c = new_connection("").expect("Couldn't open conn.");
let db = mentat_db::db::ensure_current_version(&mut c).expect("Couldn't open DB.");
// Tuple.
let start = time::PreciseTime::now();
let results = q_once(&c, &db.schema,
"[:find [?index ?cardinality]
:where [:db/txInstant :db/index ?index]
[:db/txInstant :db/cardinality ?cardinality]]",
None)
.expect("Query failed");
let end = time::PreciseTime::now();
assert_eq!(1, results.len());
if let QueryResults::Tuple(Some(ref tuple)) = results {
let cardinality_one = NamespacedKeyword::new("db.cardinality", "one");
assert_eq!(tuple.len(), 2);
assert_eq!(tuple[0], TypedValue::Boolean(true));
assert_eq!(tuple[1], TypedValue::Ref(db.schema.get_entid(&cardinality_one).unwrap()));
} else {
panic!("Expected tuple.");
}
println!("{:?}", results);
println!("Tuple took {}µs", start.to(end).num_microseconds().unwrap());
}
#[test]
fn test_coll() {
let mut c = new_connection("").expect("Couldn't open conn.");
let db = mentat_db::db::ensure_current_version(&mut c).expect("Couldn't open DB.");
// Coll.
let start = time::PreciseTime::now();
let results = q_once(&c, &db.schema,
"[:find [?e ...] :where [?e :db/ident _]]", None)
.expect("Query failed");
let end = time::PreciseTime::now();
assert_eq!(39, results.len());
if let QueryResults::Coll(ref coll) = results {
assert!(coll.iter().all(|item| item.matches_type(ValueType::Ref)));
} else {
panic!("Expected coll.");
}
println!("{:?}", results);
println!("Coll took {}µs", start.to(end).num_microseconds().unwrap());
}
#[test]
fn test_inputs() {
let mut c = new_connection("").expect("Couldn't open conn.");
let db = mentat_db::db::ensure_current_version(&mut c).expect("Couldn't open DB.");
// entids::DB_INSTALL_VALUE_TYPE = 5.
let ee = (Variable::from_valid_name("?e"), TypedValue::Ref(5));
let inputs = QueryInputs::with_value_sequence(vec![ee]);
let results = q_once(&c, &db.schema,
"[:find ?i . :in ?e :where [?e :db/ident ?i]]", inputs)
.expect("query to succeed");
if let QueryResults::Scalar(Some(TypedValue::Keyword(value))) = results {
assert_eq!(value.as_ref(), &NamespacedKeyword::new("db.install", "valueType"));
} else {
panic!("Expected scalar.");
}
}
/// Ensure that a query won't be run without all of its `:in` variables being bound.
#[test]
fn test_unbound_inputs() {
let mut c = new_connection("").expect("Couldn't open conn.");
let db = mentat_db::db::ensure_current_version(&mut c).expect("Couldn't open DB.");
// Bind the wrong var by 'mistake'.
let xx = (Variable::from_valid_name("?x"), TypedValue::Ref(5));
let inputs = QueryInputs::with_value_sequence(vec![xx]);
let results = q_once(&c, &db.schema,
"[:find ?i . :in ?e :where [?e :db/ident ?i]]", inputs);
match results {
Result::Err(Error(ErrorKind::UnboundVariables(vars), _)) => {
assert_eq!(vars, vec!["?e".to_string()].into_iter().collect());
},
_ => panic!("Expected unbound variables."),
}
}
#[test]
fn test_instants_and_uuids() {
// We assume, perhaps foolishly, that the clocks on test machines won't lose more than an
// hour while this test is running.
let start = Utc::now() + FixedOffset::west(60 * 60);
let mut c = new_connection("").expect("Couldn't open conn.");
let mut conn = Conn::connect(&mut c).expect("Couldn't open DB.");
conn.transact(&mut c, r#"[
[:db/add "s" :db/ident :foo/uuid]
[:db/add "s" :db/valueType :db.type/uuid]
[:db/add "s" :db/cardinality :db.cardinality/one]
]"#).unwrap();
conn.transact(&mut c, r#"[
[:db/add "u" :foo/uuid #uuid "cf62d552-6569-4d1b-b667-04703041dfc4"]
]"#).unwrap();
let r = conn.q_once(&mut c,
r#"[:find [?x ?u ?when]
:where [?x :foo/uuid ?u ?tx]
[?tx :db/txInstant ?when]]"#, None);
match r {
Result::Ok(QueryResults::Tuple(Some(vals))) => {
let mut vals = vals.into_iter();
match (vals.next(), vals.next(), vals.next(), vals.next()) {
(Some(TypedValue::Ref(e)),
Some(TypedValue::Uuid(u)),
Some(TypedValue::Instant(t)),
None) => {
assert!(e > 39); // There are at least this many entities in the store.
assert_eq!(Ok(u), Uuid::from_str("cf62d552-6569-4d1b-b667-04703041dfc4"));
assert!(t > start);
},
_ => panic!("Unexpected results."),
}
},
_ => panic!("Expected query to work."),
}
}
#[test]
fn test_tx() {
let mut c = new_connection("").expect("Couldn't open conn.");
let mut conn = Conn::connect(&mut c).expect("Couldn't open DB.");
conn.transact(&mut c, r#"[
[:db/add "s" :db/ident :foo/uuid]
[:db/add "s" :db/valueType :db.type/uuid]
[:db/add "s" :db/cardinality :db.cardinality/one]
]"#).expect("successful transaction");
let t = conn.transact(&mut c, r#"[
[:db/add "u" :foo/uuid #uuid "cf62d552-6569-4d1b-b667-04703041dfc4"]
]"#).expect("successful transaction");
conn.transact(&mut c, r#"[
[:db/add "u" :foo/uuid #uuid "550e8400-e29b-41d4-a716-446655440000"]
]"#).expect("successful transaction");
let r = conn.q_once(&mut c,
r#"[:find ?tx
:where [?x :foo/uuid #uuid "cf62d552-6569-4d1b-b667-04703041dfc4" ?tx]]"#, None);
match r {
Result::Ok(QueryResults::Rel(ref v)) => {
assert_eq!(*v, vec![
vec![TypedValue::Ref(t.tx_id),]
]);
},
_ => panic!("Expected query to work."),
}
}
#[test]
fn test_tx_as_input() {
let mut c = new_connection("").expect("Couldn't open conn.");
let mut conn = Conn::connect(&mut c).expect("Couldn't open DB.");
conn.transact(&mut c, r#"[
[:db/add "s" :db/ident :foo/uuid]
[:db/add "s" :db/valueType :db.type/uuid]
[:db/add "s" :db/cardinality :db.cardinality/one]
]"#).expect("successful transaction");
conn.transact(&mut c, r#"[
[:db/add "u" :foo/uuid #uuid "550e8400-e29b-41d4-a716-446655440000"]
]"#).expect("successful transaction");
let t = conn.transact(&mut c, r#"[
[:db/add "u" :foo/uuid #uuid "cf62d552-6569-4d1b-b667-04703041dfc4"]
]"#).expect("successful transaction");
conn.transact(&mut c, r#"[
[:db/add "u" :foo/uuid #uuid "267bab92-ee39-4ca2-b7f0-1163a85af1fb"]
]"#).expect("successful transaction");
let tx = (Variable::from_valid_name("?tx"), TypedValue::Ref(t.tx_id));
let inputs = QueryInputs::with_value_sequence(vec![tx]);
let r = conn.q_once(&mut c,
r#"[:find ?uuid
:in ?tx
:where [?x :foo/uuid ?uuid ?tx]]"#, inputs);
match r {
Result::Ok(QueryResults::Rel(ref v)) => {
assert_eq!(*v, vec![
vec![TypedValue::Uuid(Uuid::from_str("cf62d552-6569-4d1b-b667-04703041dfc4").expect("Valid UUID")),]
]);
},
_ => panic!("Expected query to work."),
}
}
#[test]
fn test_fulltext() {
let mut c = new_connection("").expect("Couldn't open conn.");
let mut conn = Conn::connect(&mut c).expect("Couldn't open DB.");
conn.transact(&mut c, r#"[
[:db/add "a" :db/ident :foo/term]
[:db/add "a" :db/valueType :db.type/string]
[:db/add "a" :db/fulltext false]
[:db/add "a" :db/cardinality :db.cardinality/many]
[:db/add "s" :db/ident :foo/fts]
[:db/add "s" :db/valueType :db.type/string]
[:db/add "s" :db/fulltext true]
[:db/add "s" :db/cardinality :db.cardinality/many]
]"#).unwrap();
let v = conn.transact(&mut c, r#"[
[:db/add "v" :foo/fts "hello darkness my old friend"]
[:db/add "v" :foo/fts "I've come to talk with you again"]
]"#).unwrap().tempids.get("v").cloned().expect("v was mapped");
let r = conn.q_once(&mut c,
r#"[:find [?x ?val ?score]
:where [(fulltext $ :foo/fts "darkness") [[?x ?val _ ?score]]]]"#, None);
match r {
Result::Ok(QueryResults::Tuple(Some(vals))) => {
let mut vals = vals.into_iter();
match (vals.next(), vals.next(), vals.next(), vals.next()) {
(Some(TypedValue::Ref(x)),
Some(TypedValue::String(text)),
Some(TypedValue::Double(score)),
None) => {
assert_eq!(x, v);
assert_eq!(text.as_str(), "hello darkness my old friend");
assert_eq!(score, 0.0f64.into());
},
_ => panic!("Unexpected results."),
}
},
Result::Ok(r) => panic!("Unexpected results {:?}.", r),
Result::Err(e) => panic!("Expected query to work, got {:?}.", e),
}
let a = conn.transact(&mut c, r#"[[:db/add "a" :foo/term "talk"]]"#)
.unwrap()
.tempids
.get("a").cloned()
.expect("a was mapped");
// If you use a non-constant search term, it must be bound earlier in the query.
let query = r#"[:find ?x ?val
:where
[(fulltext $ :foo/fts ?term) [[?x ?val]]]
[?a :foo/term ?term]
]"#;
let r = conn.q_once(&mut c, query, None);
match r {
Err(Error(ErrorKind::QueryError(mentat_query_algebrizer::ErrorKind::InvalidArgument(PlainSymbol(s), ty, i)), _)) => {
assert_eq!(s, "fulltext");
assert_eq!(ty, "string");
assert_eq!(i, 2);
},
_ => panic!("Expected query to fail."),
}
// Bound to the wrong type? Error.
let query = r#"[:find ?x ?val
:where
[?a :foo/term ?term]
[(fulltext $ :foo/fts ?a) [[?x ?val]]]]"#;
let r = conn.q_once(&mut c, query, None);
match r {
Err(Error(ErrorKind::QueryError(mentat_query_algebrizer::ErrorKind::InvalidArgument(PlainSymbol(s), ty, i)), _)) => {
assert_eq!(s, "fulltext");
assert_eq!(ty, "string");
assert_eq!(i, 2);
},
_ => panic!("Expected query to fail."),
}
// If it's bound, and the right type, it'll work!
let query = r#"[:find ?x ?val
:in ?a
:where
[?a :foo/term ?term]
[(fulltext $ :foo/fts ?term) [[?x ?val]]]]"#;
let inputs = QueryInputs::with_value_sequence(vec![(Variable::from_valid_name("?a"), TypedValue::Ref(a))]);
let r = conn.q_once(&mut c, query, inputs);
match r {
Result::Ok(QueryResults::Rel(rels)) => {
assert_eq!(rels, vec![
vec![TypedValue::Ref(v),
TypedValue::String("I've come to talk with you again".to_string().into()),
]
]);
},
_ => panic!("Expected query to work."),
}
}
#[test]
fn test_instant_range_query() {
let mut c = new_connection("").expect("Couldn't open conn.");
let mut conn = Conn::connect(&mut c).expect("Couldn't open DB.");
conn.transact(&mut c, r#"[
[:db/add "a" :db/ident :foo/date]
[:db/add "a" :db/valueType :db.type/instant]
[:db/add "a" :db/cardinality :db.cardinality/one]
]"#).unwrap();
let ids = conn.transact(&mut c, r#"[
[:db/add "b" :foo/date #inst "2016-01-01T11:00:00.000Z"]
[:db/add "c" :foo/date #inst "2016-06-01T11:00:01.000Z"]
[:db/add "d" :foo/date #inst "2017-01-01T11:00:02.000Z"]
[:db/add "e" :foo/date #inst "2017-06-01T11:00:03.000Z"]
]"#).unwrap().tempids;
let r = conn.q_once(&mut c,
r#"[:find [?x ...]
:order (asc ?date)
:where
[?x :foo/date ?date]
[(< ?date #inst "2017-01-01T11:00:02.000Z")]]"#, None);
match r {
Result::Ok(QueryResults::Coll(vals)) => {
assert_eq!(vals,
vec![TypedValue::Ref(*ids.get("b").unwrap()),
TypedValue::Ref(*ids.get("c").unwrap())]);
},
_ => panic!("Expected query to work."),
}
}
#[test]
fn test_aggregation_implicit_grouping() {
let mut c = new_connection("").expect("Couldn't open conn.");
let mut conn = Conn::connect(&mut c).expect("Couldn't open DB.");
conn.transact(&mut c, r#"[
[:db/add "a" :db/ident :foo/score]
[:db/add "a" :db/valueType :db.type/long]
[:db/add "a" :db/cardinality :db.cardinality/one]
[:db/add "b" :db/ident :foo/name]
[:db/add "b" :db/valueType :db.type/string]
[:db/add "b" :db/cardinality :db.cardinality/one]
[:db/add "c" :db/ident :foo/is-vegetarian]
[:db/add "c" :db/valueType :db.type/boolean]
[:db/add "c" :db/cardinality :db.cardinality/one]
[:db/add "d" :db/ident :foo/play]
[:db/add "d" :db/valueType :db.type/ref]
[:db/add "d" :db/cardinality :db.cardinality/many]
[:db/add "d" :db/unique :db.unique/value]
]"#).unwrap();
let ids = conn.transact(&mut c, r#"[
[:db/add "a" :foo/name "Alice"]
[:db/add "b" :foo/name "Beli"]
[:db/add "c" :foo/name "Carlos"]
[:db/add "d" :foo/name "Diana"]
[:db/add "a" :foo/is-vegetarian true]
[:db/add "b" :foo/is-vegetarian true]
[:db/add "c" :foo/is-vegetarian false]
[:db/add "d" :foo/is-vegetarian false]
[:db/add "aa" :foo/score 14]
[:db/add "ab" :foo/score 99]
[:db/add "ac" :foo/score 14]
[:db/add "ba" :foo/score 22]
[:db/add "bb" :foo/score 11]
[:db/add "ca" :foo/score 42]
[:db/add "da" :foo/score 5]
[:db/add "db" :foo/score 28]
[:db/add "d" :foo/play "da"]
[:db/add "d" :foo/play "db"]
[:db/add "a" :foo/play "aa"]
[:db/add "a" :foo/play "ab"]
[:db/add "a" :foo/play "ac"]
[:db/add "b" :foo/play "ba"]
[:db/add "b" :foo/play "bb"]
[:db/add "c" :foo/play "ca"]
]"#).unwrap().tempids;
// We can combine these aggregates.
let r = conn.q_once(&mut c,
r#"[:find ?x ?name (max ?score) (count ?score) (avg ?score)
:where
[?x :foo/name ?name]
[?x :foo/play ?game]
[?game :foo/score ?score]
]"#, None);
match r {
Result::Ok(QueryResults::Rel(vals)) => {
assert_eq!(vals,
vec![
vec![TypedValue::Ref(ids.get("a").cloned().unwrap()),
TypedValue::String("Alice".to_string().into()),
TypedValue::Long(99),
TypedValue::Long(3),
TypedValue::Double((127f64 / 3f64).into())],
vec![TypedValue::Ref(ids.get("b").cloned().unwrap()),
TypedValue::String("Beli".to_string().into()),
TypedValue::Long(22),
TypedValue::Long(2),
TypedValue::Double((33f64 / 2f64).into())],
vec![TypedValue::Ref(ids.get("c").cloned().unwrap()),
TypedValue::String("Carlos".to_string().into()),
TypedValue::Long(42),
TypedValue::Long(1),
TypedValue::Double(42f64.into())],
vec![TypedValue::Ref(ids.get("d").cloned().unwrap()),
TypedValue::String("Diana".to_string().into()),
TypedValue::Long(28),
TypedValue::Long(2),
TypedValue::Double((33f64 / 2f64).into())]]);
},
Result::Ok(x) => panic!("Got unexpected results {:?}", x),
Result::Err(e) => panic!("Expected query to work: got {:?}", e),
}
}
// TODO: this can't be phrased in Datalog!
/*
#[test]
fn test_corresponding_row_value_aggregation() {
// Who's youngest, via min?
let r = conn.q_once(&mut c,
r#"[:find [?name (min ?age)]
:where
[?x :foo/age ?age]
[?x :foo/name ?name]]"#, None);
match r {
Result::Ok(QueryResults::Tuple(Some(vals))) => {
assert_eq!(vals,
vec![TypedValue::String("Alice".to_string().into()),
TypedValue::Long(14)]);
},
_ => panic!("Expected query to work."),
}
// Who's oldest, via max?
let r = conn.q_once(&mut c,
r#"[:find [?name (max ?age)]
:where
[?x :foo/age ?age]
[?x :foo/name ?name]]"#, None);
match r {
Result::Ok(QueryResults::Tuple(Some(vals))) => {
assert_eq!(vals,
vec![TypedValue::String("Carlos".to_string().into()),
TypedValue::Long(42)]);
},
_ => panic!("Expected query to work."),
}
}
*/
#[test]
fn test_simple_aggregation() {
let mut c = new_connection("").expect("Couldn't open conn.");
let mut conn = Conn::connect(&mut c).expect("Couldn't open DB.");
conn.transact(&mut c, r#"[
[:db/add "a" :db/ident :foo/age]
[:db/add "a" :db/valueType :db.type/long]
[:db/add "a" :db/cardinality :db.cardinality/one]
[:db/add "b" :db/ident :foo/name]
[:db/add "b" :db/valueType :db.type/string]
[:db/add "b" :db/cardinality :db.cardinality/one]
[:db/add "c" :db/ident :foo/is-vegetarian]
[:db/add "c" :db/valueType :db.type/boolean]
[:db/add "c" :db/cardinality :db.cardinality/one]
]"#).unwrap();
let ids = conn.transact(&mut c, r#"[
[:db/add "a" :foo/name "Alice"]
[:db/add "b" :foo/name "Beli"]
[:db/add "c" :foo/name "Carlos"]
[:db/add "d" :foo/name "Diana"]
[:db/add "a" :foo/is-vegetarian true]
[:db/add "b" :foo/is-vegetarian true]
[:db/add "c" :foo/is-vegetarian false]
[:db/add "d" :foo/is-vegetarian false]
[:db/add "a" :foo/age 14]
[:db/add "b" :foo/age 22]
[:db/add "c" :foo/age 42]
[:db/add "d" :foo/age 28]
]"#).unwrap().tempids;
// Count how many vegetarians there are. This is not the same as `count-distinct`.
// Note the distinction between including `:with` and not.
let r = conn.q_once(&mut c,
r#"[:find (count ?veg)
:where
[_ :foo/is-vegetarian ?veg]
[(ground true) ?veg]]"#, None);
match r {
Result::Ok(QueryResults::Rel(vals)) => {
assert_eq!(vals, vec![vec![TypedValue::Long(1)]]);
},
Result::Ok(r) => panic!("Expected query to work, got {:?}", r),
Result::Err(e) => panic!("Expected query to work, got {:?}", e),
}
let r = conn.q_once(&mut c,
r#"[:find (count ?veg) .
:with ?person
:where
[?person :foo/is-vegetarian ?veg]
[(ground true) ?veg]]"#, None);
match r {
Result::Ok(QueryResults::Scalar(Some(val))) => {
assert_eq!(val, TypedValue::Long(2));
},
_ => panic!("Expected query to work."),
}
// What are the oldest and youngest ages?
let r = conn.q_once(&mut c,
r#"[:find [(min ?age) (max ?age)]
:where
[_ :foo/age ?age]]"#, None);
match r {
Result::Ok(QueryResults::Tuple(Some(vals))) => {
assert_eq!(vals,
vec![TypedValue::Long(14),
TypedValue::Long(42)]);
},
_ => panic!("Expected query to work."),
}
// Who's youngest, via order?
let r = conn.q_once(&mut c,
r#"[:find [?name ?age]
:order (asc ?age)
:where
[?x :foo/age ?age]
[?x :foo/name ?name]]"#, None);
match r {
Result::Ok(QueryResults::Tuple(Some(vals))) => {
assert_eq!(vals,
vec![TypedValue::String("Alice".to_string().into()),
TypedValue::Long(14)]);
},
Result::Ok(r) => panic!("Unexpected results {:?}", r),
Result::Err(e) => panic!("Expected query to work, got {:?}", e),
}
// Who's oldest, via order?
let r = conn.q_once(&mut c,
r#"[:find [?name ?age]
:order (desc ?age)
:where
[?x :foo/age ?age]
[?x :foo/name ?name]]"#, None);
match r {
Result::Ok(QueryResults::Tuple(Some(vals))) => {
assert_eq!(vals,
vec![TypedValue::String("Carlos".to_string().into()),
TypedValue::Long(42)]);
},
_ => panic!("Expected query to work."),
}
// What's the average age?
let r = conn.q_once(&mut c,
r#"[:find (avg ?age) .
:where
[_ :foo/age ?age]]"#, None);
match r {
Result::Ok(QueryResults::Scalar(Some(sum))) => {
assert_eq!(sum, TypedValue::Double(26.5f64.into()));
},
_ => panic!("Expected query to work."),
}
// What's the total age?
let r = conn.q_once(&mut c,
r#"[:find (sum ?age) .
:where
[_ :foo/age ?age]]"#, None);
match r {
Result::Ok(QueryResults::Scalar(Some(sum))) => {
assert_eq!(sum, TypedValue::Long(106));
},
_ => panic!("Expected query to work."),
}
// How many distinct names are there?
let r = conn.q_once(&mut c,
r#"[:find (count ?name) .
:where
[_ :foo/name ?name]]"#, None);
match r {
Result::Ok(QueryResults::Scalar(Some(count))) => {
assert_eq!(count, TypedValue::Long(4));
},
_ => panic!("Expected query to work."),
}
// We can use constraints, too.
// What's the average age of adults?
let r = conn.q_once(&mut c,
r#"[:find [(avg ?age) (count ?age)]
:where
[_ :foo/age ?age]
[(>= ?age 18)]]"#, None);
match r {
Result::Ok(QueryResults::Tuple(Some(vals))) => {
assert_eq!(vals, vec![TypedValue::Double((92f64 / 3f64).into()),
TypedValue::Long(3)]);
},
Result::Ok(x) => panic!("Got unexpected results {:?}", x),
Result::Err(e) => panic!("Expected query to work: got {:?}", e),
}
// Who's oldest, vegetarians or not?
let r = conn.q_once(&mut c,
r#"[:find ?veg (max ?age)
:where
[?p :foo/age ?age]
[?p :foo/is-vegetarian ?veg]]"#, None);
match r {
Result::Ok(QueryResults::Rel(vals)) => {
assert_eq!(vals, vec![
vec![TypedValue::Boolean(false), TypedValue::Long(42)],
vec![TypedValue::Boolean(true), TypedValue::Long(22)],
]);
},
Result::Ok(x) => panic!("Got unexpected results {:?}", x),
Result::Err(e) => panic!("Expected query to work: got {:?}", e),
}
}